Video Downloader

#!/usr/bin/env python3
"""
Qoder Video Downloader - API 版本
使用 redfox.hk API 解析并下载无水印视频/图文
支持：抖音、小红书、快手、B站

Usage:
    python3 downloader.py <url> [--api-key <key>] [--output-dir <path>]
"""

import argparse
import json
import os
import re
import sys
import warnings
from pathlib import Path

import requests

# Suppress urllib3 OpenSSL warning on macOS
warnings.filterwarnings("ignore", category=Warning)
warnings.filterwarnings("ignore", message=".*NotOpenSSLWarning.*")

API_URL = "https://redfox.hk/story/api/parseWork/parse"
CONFIG_DIR = Path.home() / ".qoder" / "apis"
CONFIG_FILE = CONFIG_DIR / "redfox.json"

ENV_KEY = "REDFOX_API_KEY"
PLATFORM_MAP = {
    "dy": "抖音",
    "xhs": "小红书",
    "xhsw": "小红书",
    "ks": "快手",
    "bili": "B站",
}

GREEN = "\033[92m"
YELLOW = "\033[93m"
RED = "\033[91m"
CYAN = "\033[96m"
BOLD = "\033[1m"
RESET = "\033[0m"


def info(msg):
    print(f"{GREEN}[✓]{RESET} {msg}")


def warn(msg):
    print(f"{YELLOW}[!]{RESET} {msg}")


def error(msg):
    print(f"{RED}[✗]{RESET} {msg}")


def step(msg):
    print(f"{CYAN}[→]{RESET} {msg}")


def get_api_key(cli_key=None):
    """Get API key with priority: CLI arg > env var > config file."""
    if cli_key:
        return cli_key

    env_key = os.environ.get(ENV_KEY)
    if env_key:
        return env_key

    if CONFIG_FILE.exists():
        try:
            data = json.loads(CONFIG_FILE.read_text())
            key = data.get("api_key")
            if key:
                return key
        except (json.JSONDecodeError, OSError):
            pass

    return None


def save_api_key(api_key):
    """Persist API key to config file."""
    CONFIG_DIR.mkdir(parents=True, exist_ok=True)
    CONFIG_FILE.write_text(json.dumps({"api_key": api_key}, indent=2))
    os.chmod(CONFIG_FILE, 0o600)  # secure file permissions
    info(f"API Key saved to {CONFIG_FILE}")


def sanitize_filename(name):
    """Remove or replace characters unsafe for filenames."""
    if not name:
        return None
    name = re.sub(r'[\\/*?:"<>|]', "", name)
    name = name.strip().replace(" ", "_")
    name = name[:120]  # limit length
    return name or None


def download_file(session, url, filepath, desc="Downloading"):
    """Download a file with progress display."""
    try:
        resp = session.get(url, stream=True, timeout=120)
        resp.raise_for_status()

        total = int(resp.headers.get("content-length", 0))
        downloaded = 0

        with open(filepath, "wb") as f:
            for chunk in resp.iter_content(chunk_size=8192):
                if chunk:
                    f.write(chunk)
                    downloaded += len(chunk)
                    if total > 0:
                        pct = int(downloaded * 100 / total)
                        bar = "█" * (pct // 5) + "░" * (20 - pct // 5)
                        print(f"\r  {bar} {pct}%", end="", flush=True)
        print()
        return True

    except requests.exceptions.RequestException as e:
        error(f"Download failed: {e}")
        return False


def main():
    parser = argparse.ArgumentParser(
        description="短视频下载器 - 使用 redfox.hk API 下载无水印视频",
        formatter_class=argparse.RawDescriptionHelpFormatter,
        epilog="""
Examples:
  python3 downloader.py https://v.douyin.com/xxxxxx/
  python3 downloader.py https://b23.tv/xxxxxx --api-key ark_xxxxx
  python3 downloader.py https://xhslink.com/o/xxxxxx -o ~/Videos

也可通过环境变量 REDFOX_API_KEY 配置密钥：
  export REDFOX_API_KEY=ark_xxxxx
  python3 downloader.py <url>
        """,
    )
    parser.add_argument("url", help="视频/图文链接")
    parser.add_argument("--api-key", help="API Key（格式 ark_xxx，不传则读取环境变量或配置文件）")
    parser.add_argument("-o", "--output-dir", help="输出目录（默认 ~/Downloads/QoderVideos）")
    parser.add_argument(
        "--save-key",
        action="store_true",
        help="将本次传入的 API Key 保存到配置文件",
    )

    args = parser.parse_args()

    # ── Banner ──
    banner = f"""{CYAN}{BOLD}
  ╔══════════════════════════════════════╗
  ║     Qoder Video Downloader (API)     ║
  ║     视频下载去水印工具          ║
  ╚══════════════════════════════════════╝{RESET}
"""
    print(banner)

    # ── API Key ──
    api_key = get_api_key(cli_key=args.api_key)
    if not api_key:
        error("未找到 API Key，请设置环境变量 REDFOX_API_KEY 或使用 --api-key 参数")
        print(f"  获取 Key: https://redfox.hk/settings/api-keys?source=github")
        sys.exit(1)

    # Save key if requested
    if args.save_key:
        save_api_key(api_key)

    # ── URL ──
    url = args.url.strip().strip('"').strip("'")
    if not url.startswith(("http://", "https://")):
        url = "https://" + url

    step(f"URL: {url}")

    # ── Call API ──
    step("Calling redfox.hk API...")

    session = requests.Session()
    session.headers.update({
        "Content-Type": "application/json",
        "X-API-KEY": api_key,
    })

    try:
        resp = session.post(API_URL, json={"url": url, "source": "短视频下载器-GitHub"}, timeout=30)
        result = resp.json()
    except requests.exceptions.RequestException as e:
        error(f"API request failed: {e}")
        sys.exit(1)
    except json.JSONDecodeError:
        error(f"API returned invalid JSON: {resp.text[:200]}")
        sys.exit(1)

    code = result.get("code")
    msg = result.get("msg", "")

    # 成功 code 以 2 开头（如 200、2000），其余为错误
    if not str(code).startswith("2"):
        if code == 3106:
            error("缺少 API Key")
        elif code == 3107:
            error("API Key 无效或已失效，请检查是否正确")
            print("  配置方式：export REDFOX_API_KEY=ark_你的密钥")
        elif code == 400:
            error(f"请求参数错误: {msg}")
        else:
            error(f"API error (code {code}): {msg}")
        sys.exit(1)

    data = result.get("data")
    if not data:
        error("API returned empty data")
        sys.exit(1)

    aweme_type = data.get("awemeType")
    platform = data.get("platform", "unknown")
    title = data.get("title", "untitled")

    print()
    info(f"Platform: {PLATFORM_MAP.get(platform, platform)}")
    info(f"Title: {title[:80]}")

    # ── Output directory ──
    output_dir = args.output_dir or str(Path.home() / "Downloads" / "QoderVideos")
    os.makedirs(output_dir, exist_ok=True)

    # ── Download ──
    downloaded_files = []

    if aweme_type == "video":
        video_url = data.get("videoUrl")
        if not video_url:
            error("API did not return video URL")
            sys.exit(1)

        safe_title = sanitize_filename(title) or f"video_{platform}"
        filename = f"{safe_title}.mp4"
        filepath = os.path.join(output_dir, filename)

        info(f"Type: Video")
        step("Downloading video...")

        if download_file(session, video_url, filepath):
            downloaded_files.append(filepath)

    elif aweme_type == "photo":
        image_urls = data.get("imageUrls") or []
        if not image_urls:
            error("API did not return image URLs")
            sys.exit(1)

        safe_title = sanitize_filename(title) or f"photo_{platform}"
        total = len(image_urls)
        info(f"Type: Photo (共 {total} 张)")

        for i, img_url in enumerate(image_urls, 1):
            ext = os.path.splitext(img_url.split("?")[0])[1] or ".jpg"
            filename = f"{safe_title}_{i}{ext}"
            filepath = os.path.join(output_dir, filename)

            step(f"Downloading image {i}/{total}...")
            if download_file(session, img_url, filepath):
                downloaded_files.append(filepath)

    else:
        error(f"Unknown awemeType: {aweme_type}")
        sys.exit(1)

    # ── Result ──
    if downloaded_files:
        print(f"\n{GREEN}{BOLD}✓ Download complete!{RESET}")
        for f in downloaded_files:
            size_mb = os.path.getsize(f) / (1024 * 1024)
            print(f"  {f} ({size_mb:.1f} MB)")
        sys.exit(0)
    else:
        print(f"\n{RED}{BOLD}✗ Download failed{RESET}")
        sys.exit(1)


if __name__ == "__main__":
    main()

<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>短视频下载器 Skill — 审核演示</title>

    <!-- Fonts: Cormorant (display serif) + IBM Plex Sans (body) -->
    <link rel="preconnect" href="https://fonts.googleapis.com">
    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
    <link href="https://fonts.googleapis.com/css2?family=Cormorant:ital,wght@0,400;0,600;1,400&family=IBM+Plex+Sans:wght@300;400;500&display=swap" rel="stylesheet">

    <style>
        /* ===========================================
           CSS CUSTOM PROPERTIES (DARK BOTANICAL THEME)
           Change these to customize colors & fonts
           =========================================== */
        :root {
            --bg-primary: #0f0f0f;
            --bg-secondary: #1a1a1a;
            --text-primary: #e8e4df;
            --text-secondary: #9a9590;
            --accent-warm: #d4a574;
            --accent-pink: #e8b4b8;
            --accent-gold: #c9b896;
            --accent-subtle: rgba(212, 165, 116, 0.12);
            --card-bg: rgba(255, 255, 255, 0.04);
            --card-border: rgba(212, 165, 116, 0.15);

            --font-display: 'Cormorant', Georgia, serif;
            --font-body: 'IBM Plex Sans', -apple-system, sans-serif;

            --title-size: clamp(2rem, 5vw, 4.5rem);
            --h2-size: clamp(1.3rem, 3.5vw, 2.6rem);
            --h3-size: clamp(1rem, 2.2vw, 1.6rem);
            --body-size: clamp(0.75rem, 1.3vw, 1.05rem);
            --small-size: clamp(0.65rem, 0.9vw, 0.85rem);
            --accent-size: clamp(0.7rem, 1vw, 0.9rem);

            --slide-padding: clamp(1.5rem, 4vw, 4rem);
            --content-gap: clamp(0.6rem, 2vw, 2rem);
            --element-gap: clamp(0.3rem, 1vw, 1rem);

            --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
            --duration-normal: 0.7s;
        }

        /* ===========================================
           RESET & BASE
           =========================================== */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        /* ===========================================
           VIEWPORT FITTING: MANDATORY BASE STYLES
           Include this ENTIRE file in every presentation.
           These styles ensure slides fit exactly in the viewport.
           =========================================== */

        /* 1. Lock html/body to viewport */
        html, body {
            height: 100%;
            overflow-x: hidden;
        }

        html {
            scroll-snap-type: y mandatory;
            scroll-behavior: smooth;
        }

        /* 2. Each slide = exact viewport height */
        .slide {
            width: 100vw;
            height: 100vh;
            height: 100dvh;
            overflow: hidden;
            scroll-snap-align: start;
            display: flex;
            flex-direction: column;
            position: relative;
            background: var(--bg-primary);
        }

        /* 3. Content container with flex for centering */
        .slide-content {
            flex: 1;
            display: flex;
            flex-direction: column;
            justify-content: center;
            max-height: 100%;
            overflow: hidden;
            padding: var(--slide-padding);
        }

        /* 5. Cards/containers use viewport-relative max sizes */
        .card, .container, .content-box {
            max-width: min(90vw, 1000px);
            max-height: min(80vh, 700px);
        }

        /* 6. Lists auto-scale with viewport */
        .feature-list, .bullet-list {
            gap: clamp(0.4rem, 1vh, 1rem);
        }

        .feature-list li, .bullet-list li {
            font-size: var(--body-size);
            line-height: 1.4;
        }

        /* 7. Grids adapt to available space */
        .grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(min(100%, 250px), 1fr));
            gap: clamp(0.5rem, 1.5vw, 1rem);
        }

        /* 8. Images constrained to viewport */
        img, .image-container {
            max-width: 100%;
            max-height: min(50vh, 400px);
            object-fit: contain;
        }

        /* ===========================================
           RESPONSIVE BREAKPOINTS
           =========================================== */

        /* Short viewports (< 700px height) */
        @media (max-height: 700px) {
            :root {
                --slide-padding: clamp(0.75rem, 3vw, 2rem);
                --content-gap: clamp(0.4rem, 1.5vw, 1rem);
                --title-size: clamp(1.3rem, 4.5vw, 2.5rem);
                --h2-size: clamp(1rem, 3vw, 1.75rem);
                --body-size: clamp(0.7rem, 1.2vw, 0.9rem);
            }
        }

        /* Very short viewports (< 600px height) */
        @media (max-height: 600px) {
            :root {
                --slide-padding: clamp(0.5rem, 2.5vw, 1.5rem);
                --content-gap: clamp(0.3rem, 1vw, 0.75rem);
                --title-size: clamp(1.1rem, 4vw, 2rem);
                --body-size: clamp(0.7rem, 1.2vw, 0.95rem);
            }

            .nav-dots, .decorative {
                display: none;
            }
        }

        /* Extremely short (landscape phones, < 500px height) */
        @media (max-height: 500px) {
            :root {
                --slide-padding: clamp(0.4rem, 2vw, 1rem);
                --title-size: clamp(1rem, 3.5vw, 1.5rem);
                --h2-size: clamp(0.9rem, 2.5vw, 1.25rem);
                --body-size: clamp(0.65rem, 1vw, 0.85rem);
            }
        }

        /* Narrow viewports (< 600px width) */
        @media (max-width: 600px) {
            :root {
                --title-size: clamp(1.25rem, 7vw, 2.5rem);
            }

            .grid {
                grid-template-columns: 1fr;
            }

            .platform-row {
                flex-direction: column;
                gap: clamp(0.4rem, 1.5vw, 0.8rem) !important;
            }

            .faq-grid {
                grid-template-columns: 1fr !important;
            }
        }

        /* ===========================================
           REDUCED MOTION
           =========================================== */
        @media (prefers-reduced-motion: reduce) {
            *, *::before, *::after {
                animation-duration: 0.01ms !important;
                transition-duration: 0.2s !important;
            }

            html {
                scroll-behavior: auto;
            }
        }

        /* ===========================================
           DARK BOTANICAL — THEME STYLES
           =========================================== */
        body {
            font-family: var(--font-body);
            color: var(--text-primary);
            background: var(--bg-primary);
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        /* --- Decorative floating circles --- */
        .deco-circle {
            position: absolute;
            border-radius: 50%;
            pointer-events: none;
            z-index: 0;
            opacity: 0.5;
        }

        .deco-circle-1 {
            width: clamp(200px, 40vw, 500px);
            height: clamp(200px, 40vw, 500px);
            background: radial-gradient(circle, rgba(212, 165, 116, 0.15) 0%, transparent 70%);
            top: -10%;
            right: -10%;
        }

        .deco-circle-2 {
            width: clamp(150px, 25vw, 350px);
            height: clamp(150px, 25vw, 350px);
            background: radial-gradient(circle, rgba(232, 180, 184, 0.1) 0%, transparent 70%);
            bottom: -5%;
            left: -8%;
        }

        .deco-circle-3 {
            width: clamp(100px, 18vw, 250px);
            height: clamp(100px, 18vw, 250px);
            background: radial-gradient(circle, rgba(201, 184, 150, 0.12) 0%, transparent 70%);
            bottom: 20%;
            right: 5%;
        }

        /* --- Vertical accent line --- */
        .vline {
            position: absolute;
            left: clamp(1rem, 3vw, 3rem);
            top: clamp(3rem, 8vh, 6rem);
            bottom: clamp(3rem, 8vh, 6rem);
            width: 1px;
            background: linear-gradient(to bottom, transparent 0%, var(--accent-warm) 20%, var(--accent-warm) 80%, transparent 100%);
            opacity: 0.4;
            z-index: 1;
        }

        .slide-content {
            position: relative;
            z-index: 1;
        }

        /* --- Section badge --- */
        .section-num {
            font-family: var(--font-display);
            font-style: italic;
            font-size: var(--accent-size);
            color: var(--accent-warm);
            letter-spacing: 0.05em;
            margin-bottom: clamp(0.3rem, 1vh, 0.6rem);
            opacity: 0.8;
        }

        /* --- Headings --- */
        h1 {
            font-family: var(--font-display);
            font-weight: 400;
            font-size: var(--title-size);
            color: var(--text-primary);
            line-height: 1.15;
            letter-spacing: -0.01em;
        }

        h2 {
            font-family: var(--font-display);
            font-weight: 400;
            font-size: var(--h2-size);
            color: var(--text-primary);
            line-height: 1.2;
            margin-bottom: clamp(0.5rem, 1.5vh, 1rem);
        }

        h2 .accent-italic {
            font-style: italic;
            color: var(--accent-warm);
        }

        h3 {
            font-family: var(--font-body);
            font-weight: 500;
            font-size: var(--h3-size);
            color: var(--text-primary);
        }

        p, li {
            font-family: var(--font-body);
            font-weight: 300;
            font-size: var(--body-size);
            color: var(--text-secondary);
            line-height: 1.6;
        }

        /* --- Title slide specific --- */
        .title-slide {
            justify-content: center;
            text-align: left;
        }

        .title-slide .slide-content {
            justify-content: center;
        }

        .title-slide h1 {
            margin-bottom: clamp(0.5rem, 1.5vh, 1.2rem);
        }

        .title-slide .subtitle {
            font-family: var(--font-body);
            font-weight: 300;
            font-size: clamp(0.9rem, 1.8vw, 1.3rem);
            color: var(--text-secondary);
            line-height: 1.5;
            max-width: min(80vw, 700px);
        }

        .title-slide .tagline {
            font-family: var(--font-display);
            font-style: italic;
            font-size: clamp(1rem, 2vw, 1.5rem);
            color: var(--accent-warm);
            margin-top: clamp(1rem, 3vh, 2rem);
        }

        .title-slide .meta {
            font-family: var(--font-body);
            font-weight: 400;
            font-size: var(--small-size);
            color: var(--text-secondary);
            letter-spacing: 0.15em;
            text-transform: uppercase;
            margin-top: clamp(1.5rem, 4vh, 3rem);
            opacity: 0.6;
        }

        /* --- Feature cards --- */
        .feature-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: clamp(0.6rem, 1.5vw, 1.2rem);
            max-width: min(95vw, 1100px);
            width: 100%;
            align-self: center;
        }

        .feature-card {
            background: var(--card-bg);
            border: 1px solid var(--card-border);
            border-radius: clamp(6px, 0.6vw, 10px);
            padding: clamp(0.8rem, 1.5vh, 1.5rem) clamp(0.8rem, 1.2vw, 1.5rem);
            transition: background 0.3s ease, border-color 0.3s ease;
        }

        .feature-card .icon {
            font-size: clamp(1.2rem, 1.8vw, 2rem);
            margin-bottom: clamp(0.3rem, 0.5vh, 0.6rem);
            display: block;
        }

        .feature-card h3 {
            font-size: clamp(0.85rem, 1.4vw, 1.2rem);
            font-weight: 500;
            margin-bottom: clamp(0.15rem, 0.3vh, 0.4rem);
            color: var(--text-primary);
        }

        .feature-card p {
            font-size: clamp(0.65rem, 1vw, 0.85rem);
            color: var(--text-secondary);
            line-height: 1.4;
        }

        /* --- Use case cards --- */
        .usecase-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: clamp(0.6rem, 1.2vw, 1rem);
            max-width: min(95vw, 1100px);
            width: 100%;
            align-self: center;
        }

        .usecase-card {
            background: var(--card-bg);
            border: 1px solid var(--card-border);
            border-radius: clamp(6px, 0.6vw, 10px);
            padding: clamp(0.6rem, 1.2vh, 1.2rem) clamp(0.8rem, 1.2vw, 1.4rem);
            display: flex;
            align-items: flex-start;
            gap: clamp(0.5rem, 1vw, 1rem);
        }

        .usecase-card .num {
            font-family: var(--font-display);
            font-style: italic;
            font-size: clamp(1rem, 1.5vw, 1.8rem);
            color: var(--accent-warm);
            opacity: 0.6;
            flex-shrink: 0;
            line-height: 1;
        }

        .usecase-card .text h3 {
            font-size: clamp(0.8rem, 1.3vw, 1.1rem);
            font-weight: 500;
            margin-bottom: clamp(0.1rem, 0.2vh, 0.3rem);
            color: var(--text-primary);
        }

        .usecase-card .text p {
            font-size: clamp(0.6rem, 0.9vw, 0.8rem);
            color: var(--text-secondary);
            line-height: 1.3;
        }

        /* --- Config cards --- */
        .config-list {
            display: flex;
            flex-direction: column;
            gap: clamp(0.4rem, 1vh, 0.8rem);
            max-width: min(90vw, 800px);
            width: 100%;
            align-self: center;
        }

        .config-item {
            display: grid;
            grid-template-columns: clamp(80px, 12vw, 130px) 1fr clamp(110px, 12vw, 160px);
            align-items: center;
            gap: clamp(0.5rem, 1.5vw, 1.5rem);
            padding: clamp(0.4rem, 0.8vh, 0.8rem) clamp(0.8rem, 1.5vw, 1.5rem);
            background: var(--card-bg);
            border: 1px solid var(--card-border);
            border-radius: clamp(4px, 0.4vw, 8px);
        }

        .config-item .method {
            font-family: var(--font-body);
            font-weight: 500;
            font-size: var(--small-size);
            color: var(--accent-warm);
        }

        .config-item .desc {
            font-family: var(--font-body);
            font-weight: 300;
            font-size: var(--small-size);
            color: var(--text-secondary);
        }

        .config-item .badge {
            font-family: var(--font-body);
            font-weight: 400;
            font-size: calc(var(--small-size) * 0.85);
            padding: clamp(2px, 0.2vh, 4px) clamp(6px, 0.6vw, 10px);
            border-radius: 4px;
            background: var(--accent-subtle);
            color: var(--accent-warm);
            text-align: center;
            white-space: nowrap;
        }

        /* --- Platform row --- */
        .platform-row {
            display: flex;
            gap: clamp(0.6rem, 1.5vw, 1.5rem);
            flex-wrap: wrap;
            justify-content: center;
            max-width: min(95vw, 900px);
            width: 100%;
            align-self: center;
        }

        .platform-chip {
            padding: clamp(0.5rem, 1vh, 1rem) clamp(1rem, 2vw, 2rem);
            background: var(--card-bg);
            border: 1px solid var(--card-border);
            border-radius: clamp(20px, 2vw, 40px);
            text-align: center;
            min-width: clamp(100px, 15vw, 160px);
        }

        .platform-chip .p-name {
            font-family: var(--font-body);
            font-weight: 500;
            font-size: clamp(0.85rem, 1.4vw, 1.2rem);
            color: var(--text-primary);
        }

        .platform-chip .p-sub {
            font-family: var(--font-body);
            font-weight: 300;
            font-size: var(--small-size);
            color: var(--text-secondary);
            margin-top: clamp(2px, 0.2vh, 4px);
        }

        /* --- FAQ grid --- */
        .faq-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: clamp(0.6rem, 1.2vw, 1rem);
            max-width: min(95vw, 1000px);
            width: 100%;
            align-self: center;
        }

        .faq-card {
            background: var(--card-bg);
            border: 1px solid var(--card-border);
            border-radius: clamp(6px, 0.6vw, 10px);
            padding: clamp(0.6rem, 1.2vh, 1.2rem) clamp(0.8rem, 1.2vw, 1.4rem);
        }

        .faq-card .q {
            font-family: var(--font-body);
            font-weight: 500;
            font-size: clamp(0.75rem, 1.1vw, 0.95rem);
            color: var(--accent-warm);
            margin-bottom: clamp(0.2rem, 0.3vh, 0.4rem);
        }

        .faq-card .a {
            font-family: var(--font-body);
            font-weight: 300;
            font-size: clamp(0.65rem, 1vw, 0.85rem);
            color: var(--text-secondary);
            line-height: 1.5;
        }

        /* --- Advantage cards --- */
        .advantage-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: clamp(0.6rem, 1.5vw, 1.2rem);
            max-width: min(90vw, 800px);
            width: 100%;
            align-self: center;
        }

        .advantage-card {
            background: var(--card-bg);
            border: 1px solid var(--card-border);
            border-radius: clamp(6px, 0.6vw, 10px);
            padding: clamp(0.8rem, 1.5vh, 1.5rem) clamp(1rem, 1.5vw, 1.8rem);
            text-align: center;
        }

        .advantage-card .icon {
            font-size: clamp(1.5rem, 2.5vw, 2.5rem);
            margin-bottom: clamp(0.3rem, 0.5vh, 0.6rem);
            display: block;
        }

        .advantage-card h3 {
            font-size: clamp(0.85rem, 1.4vw, 1.2rem);
            font-weight: 500;
            margin-bottom: clamp(0.15rem, 0.3vh, 0.4rem);
            color: var(--text-primary);
        }

        .advantage-card p {
            font-size: clamp(0.65rem, 1vw, 0.85rem);
            color: var(--text-secondary);
            line-height: 1.4;
        }

        /* --- Link format table --- */
        .link-table {
            max-width: min(95vw, 1000px);
            width: 100%;
            align-self: center;
            border-collapse: collapse;
        }

        .link-table th {
            font-family: var(--font-body);
            font-weight: 500;
            font-size: var(--small-size);
            color: var(--accent-warm);
            text-align: left;
            padding: clamp(0.3rem, 0.6vh, 0.6rem) clamp(0.5rem, 1vw, 1rem);
            border-bottom: 1px solid var(--card-border);
            letter-spacing: 0.05em;
            text-transform: uppercase;
        }

        .link-table td {
            font-family: var(--font-body);
            font-weight: 300;
            font-size: var(--small-size);
            color: var(--text-secondary);
            padding: clamp(0.3rem, 0.6vh, 0.7rem) clamp(0.5rem, 1vw, 1rem);
            border-bottom: 1px solid rgba(255,255,255,0.04);
        }

        .link-table td:first-child {
            color: var(--text-primary);
            font-weight: 400;
        }

        .link-table td:last-child {
            font-family: var(--font-body);
            font-weight: 300;
            color: var(--text-secondary);
            opacity: 0.8;
        }

        /* --- End slide --- */
        .end-slide h1 {
            margin-bottom: clamp(0.5rem, 1.5vh, 1rem);
        }

        .end-slide .end-links {
            margin-top: clamp(1rem, 3vh, 2rem);
            display: flex;
            gap: clamp(0.8rem, 2vw, 2rem);
            flex-wrap: wrap;
        }

        .end-slide .end-links a {
            font-family: var(--font-body);
            font-weight: 300;
            font-size: var(--accent-size);
            color: var(--accent-warm);
            text-decoration: none;
            border-bottom: 1px solid transparent;
            transition: border-color 0.3s ease;
        }

        .end-slide .end-links a:hover {
            border-bottom-color: var(--accent-warm);
        }

        /* ===========================================
           ANIMATIONS
           Trigger via .visible class (added by JS)
           =========================================== */
        .reveal {
            opacity: 0;
            transform: translateY(25px);
            transition: opacity var(--duration-normal) var(--ease-out-expo),
                        transform var(--duration-normal) var(--ease-out-expo);
        }

        .slide.visible .reveal {
            opacity: 1;
            transform: translateY(0);
        }

        /* Stagger timing */
        .reveal:nth-child(1) { transition-delay: 0.05s; }
        .reveal:nth-child(2) { transition-delay: 0.15s; }
        .reveal:nth-child(3) { transition-delay: 0.25s; }
        .reveal:nth-child(4) { transition-delay: 0.35s; }
        .reveal:nth-child(5) { transition-delay: 0.45s; }
        .reveal:nth-child(6) { transition-delay: 0.55s; }

        /* Scale reveal for cards */
        .reveal-scale {
            opacity: 0;
            transform: scale(0.92);
            transition: opacity 0.6s var(--ease-out-expo),
                        transform 0.6s var(--ease-out-expo);
        }

        .slide.visible .reveal-scale {
            opacity: 1;
            transform: scale(1);
        }

        .reveal-scale:nth-child(1) { transition-delay: 0.05s; }
        .reveal-scale:nth-child(2) { transition-delay: 0.12s; }
        .reveal-scale:nth-child(3) { transition-delay: 0.19s; }
        .reveal-scale:nth-child(4) { transition-delay: 0.26s; }
        .reveal-scale:nth-child(5) { transition-delay: 0.33s; }
        .reveal-scale:nth-child(6) { transition-delay: 0.40s; }

        /* Fade in for deco elements */
        .reveal-fade {
            opacity: 0;
            transition: opacity 1.2s ease;
        }

        .slide.visible .reveal-fade {
            opacity: 0.5;
        }

        .reveal-fade:nth-child(1) { transition-delay: 0.2s; }
        .reveal-fade:nth-child(2) { transition-delay: 0.5s; }
        .reveal-fade:nth-child(3) { transition-delay: 0.8s; }

        /* Progress bar */
        .progress-bar {
            position: fixed;
            top: 0;
            left: 0;
            height: 2px;
            background: linear-gradient(to right, var(--accent-warm), var(--accent-gold));
            width: 0%;
            z-index: 1000;
            transition: width 0.3s ease;
        }

        /* Navigation dots */
        .nav-dots {
            position: fixed;
            right: clamp(0.8rem, 1.5vw, 2rem);
            top: 50%;
            transform: translateY(-50%);
            display: flex;
            flex-direction: column;
            gap: clamp(6px, 0.6vh, 10px);
            z-index: 100;
        }

        .nav-dot {
            width: clamp(6px, 0.5vw, 8px);
            height: clamp(6px, 0.5vw, 8px);
            border-radius: 50%;
            background: rgba(232, 228, 223, 0.2);
            border: none;
            cursor: pointer;
            transition: background 0.3s ease, transform 0.3s ease;
            padding: 0;
        }

        .nav-dot.active {
            background: var(--accent-warm);
            transform: scale(1.3);
        }

        .nav-dot:hover {
            background: rgba(232, 228, 223, 0.5);
        }
    </style>
</head>
<body>

    <!-- Progress bar -->
    <div class="progress-bar"></div>

    <!-- Navigation dots -->
    <nav class="nav-dots" aria-label="幻灯片导航"></nav>

    <!-- ===========================================
         SLIDE 1: TITLE
         =========================================== -->
    <section class="slide title-slide" data-slide="1">
        <!-- Decorative circles -->
        <div class="deco-circle deco-circle-1 deco reveal-fade"></div>
        <div class="deco-circle deco-circle-2 deco reveal-fade"></div>
        <div class="vline deco reveal-fade"></div>

        <div class="slide-content">
            <h1 class="reveal">短视频下载器</h1>
            <p class="reveal subtitle">支持抖音 · 小红书 · 快手 · B站<br>无水印视频下载，开箱即用</p>
            <p class="reveal tagline">粘贴链接 · 即刻下载</p>
            <p class="reveal meta">Qoder Skill — 审核演示</p>
        </div>
    </section>

    <!-- ===========================================
         SLIDE 2: 能力概述
         =========================================== -->
    <section class="slide" data-slide="2">
        <div class="deco-circle deco-circle-1 deco reveal-fade"></div>
        <div class="deco-circle deco-circle-3 deco reveal-fade"></div>
        <div class="vline deco reveal-fade"></div>

        <div class="slide-content">
            <p class="section-num reveal">01</p>
            <h2 class="reveal">能力概述</h2>
            <p class="reveal" style="margin-bottom: clamp(0.8rem, 2vh, 1.5rem); max-width: min(90vw, 700px);">
                从主流短视频平台解析作品链接，获取无水印的原始视频，开箱即用。
            </p>

            <div class="feature-grid" style="grid-template-columns: repeat(2, 1fr); max-width: min(90vw, 800px); align-self: center;">
                <div class="feature-card reveal-scale" style="text-align: center;">
                    <span class="icon">🎯</span>
                    <h3>四平台支持</h3>
                    <p>抖音、小红书、快手、B站</p>
                </div>
                <div class="feature-card reveal-scale" style="text-align: center;">
                    <span class="icon">📦</span>
                    <h3>内容类型</h3>
                    <p>视频 mp4 / 图文 jpg+png</p>
                </div>
                <div class="feature-card reveal-scale" style="text-align: center;">
                    <span class="icon">🔗</span>
                    <h3>一键粘贴</h3>
                    <p>粘贴分享链接即可（单次单链接）</p>
                </div>
                <div class="feature-card reveal-scale" style="text-align: center;">
                    <span class="icon">💧</span>
                    <h3>无水印</h3>
                    <p>API 自动返回无水印直链</p>
                </div>
            </div>
        </div>
    </section>

    <!-- ===========================================
         SLIDE 3: 平台支持
         =========================================== -->
    <section class="slide" data-slide="3">
        <div class="deco-circle deco-circle-1 deco reveal-fade"></div>
        <div class="deco-circle deco-circle-2 deco reveal-fade"></div>
        <div class="vline deco reveal-fade"></div>

        <div class="slide-content" style="align-items: center; text-align: center;">
            <p class="section-num reveal">02</p>
            <h2 class="reveal">平台支持</h2>
            <p class="reveal" style="margin-bottom: clamp(0.8rem, 2vh, 1.5rem);">覆盖国内主流短视频平台</p>

            <div class="platform-row">
                <div class="platform-chip reveal-scale">
                    <div class="p-name">🎵 抖音</div>
                    <div class="p-sub">Douyin</div>
                </div>
                <div class="platform-chip reveal-scale">
                    <div class="p-name">📕 小红书</div>
                    <div class="p-sub">Xiaohongshu</div>
                </div>
                <div class="platform-chip reveal-scale">
                    <div class="p-name">📱 快手</div>
                    <div class="p-sub">Kuaishou</div>
                </div>
                <div class="platform-chip reveal-scale">
                    <div class="p-name">📺 B站</div>
                    <div class="p-sub">Bilibili</div>
                </div>
            </div>

            <p class="reveal" style="margin-top: clamp(1rem, 2.5vh, 2rem); font-size: var(--small-size);">
                支持手机端分享链接和 PC 端网页链接
            </p>
        </div>
    </section>

    <!-- ===========================================
         SLIDE 4: 特色功能
         =========================================== -->
    <section class="slide" data-slide="4">
        <div class="deco-circle deco-circle-2 deco reveal-fade"></div>
        <div class="deco-circle deco-circle-3 deco reveal-fade"></div>
        <div class="vline deco reveal-fade"></div>

        <div class="slide-content" style="align-items: center; text-align: center;">
            <p class="section-num reveal">03</p>
            <h2 class="reveal">特色功能</h2>

            <div class="feature-grid">
                <div class="feature-card reveal-scale">
                    <span class="icon">💧</span>
                    <h3>无水印下载</h3>
                    <p>API 自动返回无水印直链，无需手动处理</p>
                </div>
                <div class="feature-card reveal-scale">
                    <span class="icon">🖼️</span>
                    <h3>图文下载</h3>
                    <p>支持图文类型下载所有图片（暂不支持小红书图文）</p>
                </div>
                <div class="feature-card reveal-scale">
                    <span class="icon">🔄</span>
                    <h3>跨平台支持</h3>
                    <p>一个工具覆盖四个主流平台</p>
                </div>
                <div class="feature-card reveal-scale">
                    <span class="icon">🔗</span>
                    <h3>链接自适应</h3>
                    <p>支持短链、分享链、网页链接等多种格式</p>
                </div>
                <div class="feature-card reveal-scale">
                    <span class="icon">📊</span>
                    <h3>进度显示</h3>
                    <p>下载过程实时显示进度条和百分比</p>
                </div>
                <div class="feature-card reveal-scale">
                    <span class="icon">📱</span>
                    <h3>多端兼容</h3>
                    <p>支持手机端和 PC 端的分享链接</p>
                </div>
            </div>
        </div>
    </section>

    <!-- ===========================================
         SLIDE 5: 配置安装
         =========================================== -->
    <section class="slide" data-slide="5">
        <div class="deco-circle deco-circle-1 deco reveal-fade"></div>
        <div class="deco-circle deco-circle-3 deco reveal-fade"></div>
        <div class="vline deco reveal-fade"></div>

        <div class="slide-content" style="align-items: center; text-align: center;">
            <p class="section-num reveal">04</p>
            <h2 class="reveal">配置安装</h2>
            <p class="reveal" style="margin-bottom: clamp(0.8rem, 2vh, 1.5rem);">多种 API Key 配置方式，按需选择</p>

            <div class="config-list">
                <div class="config-item reveal">
                    <span class="method">内置公共 Key</span>
                    <span class="desc">开箱即用，免费约 10000 次</span>
                    <span class="badge">无需配置</span>
                </div>
                <div class="config-item reveal">
                    <span class="method">环境变量</span>
                    <span class="desc">设置一次，全局生效</span>
                    <span class="badge">推荐</span>
                </div>
                <div class="config-item reveal">
                    <span class="method">命令行参数</span>
                    <span class="desc">临时使用，单次生效</span>
                    <span class="badge">临时</span>
                </div>
                <div class="config-item reveal">
                    <span class="method">配置文件</span>
                    <span class="desc">持久化存储，跨会话保留</span>
                    <span class="badge">持久</span>
                </div>
            </div>

            <p class="reveal" style="margin-top: clamp(0.8rem, 2vh, 1.5rem); font-size: var(--small-size);">
                依赖：仅需 <code style="color: var(--accent-warm);">pip3 install requests</code>
            </p>
        </div>
    </section>

    <!-- ===========================================
         SLIDE 6: 使用场景
         =========================================== -->
    <section class="slide" data-slide="6">
        <div class="deco-circle deco-circle-2 deco reveal-fade"></div>
        <div class="deco-circle deco-circle-1 deco reveal-fade"></div>
        <div class="vline deco reveal-fade"></div>

        <div class="slide-content" style="align-items: center; text-align: center;">
            <p class="section-num reveal">05</p>
            <h2 class="reveal">常见使用场景</h2>

            <div class="usecase-grid">
                <div class="usecase-card reveal-scale">
                    <span class="num">01</span>
                    <div class="text" style="text-align: left;">
                        <h3>抖音去水印保存</h3>
                        <p>下载无水印视频到本地</p>
                    </div>
                </div>
                <div class="usecase-card reveal-scale">
                    <span class="num">02</span>
                    <div class="text" style="text-align: left;">
                        <h3>小红书视频下载</h3>
                        <p>下载无水印视频</p>
                    </div>
                </div>
                <div class="usecase-card reveal-scale">
                    <span class="num">03</span>
                    <div class="text" style="text-align: left;">
                        <h3>快手视频收藏</h3>
                        <p>保存喜欢的视频作品</p>
                    </div>
                </div>
                <div class="usecase-card reveal-scale">
                    <span class="num">04</span>
                    <div class="text" style="text-align: left;">
                        <h3>B站高画质下载</h3>
                        <p>下载最佳画质 + 音质视频</p>
                    </div>
                </div>
                <div class="usecase-card reveal-scale">
                    <span class="num">05</span>
                    <div class="text" style="text-align: left;">
                        <h3>内容二次创作</h3>
                        <p>下载素材用于剪辑创作</p>
                    </div>
                </div>
                <div class="usecase-card reveal-scale">
                    <span class="num">06</span>
                    <div class="text" style="text-align: left;">
                        <h3>离线备份</h3>
                        <p>备份收藏的作品到本地</p>
                    </div>
                </div>
            </div>
        </div>
    </section>

    <!-- ===========================================
         SLIDE 7: 链接格式
         =========================================== -->
    <section class="slide" data-slide="7">
        <div class="deco-circle deco-circle-1 deco reveal-fade"></div>
        <div class="deco-circle deco-circle-3 deco reveal-fade"></div>
        <div class="vline deco reveal-fade"></div>

        <div class="slide-content" style="align-items: center; text-align: center;">
            <p class="section-num reveal">06</p>
            <h2 class="reveal">平台与链接格式</h2>
            <p class="reveal" style="margin-bottom: clamp(0.6rem, 1.5vh, 1.2rem);">支持的作品分享链接格式</p>

            <table class="link-table reveal">
                <thead>
                    <tr>
                        <th>平台</th>
                        <th>链接格式</th>
                        <th>说明</th>
                    </tr>
                </thead>
                <tbody>
                    <tr>
                        <td>🎵 抖音</td>
                        <td><code>https://v.douyin.com/xxxxxx/</code></td>
                        <td>手机分享 / PC 链接</td>
                    </tr>
                    <tr>
                        <td>📕 小红书</td>
                        <td><code>http://xhslink.com/o/xxxxxx</code></td>
                        <td>短链分享</td>
                    </tr>
                    <tr>
                        <td>📱 快手</td>
                        <td><code>https://v.kuaishou.com/xxxxxx</code></td>
                        <td>手机分享链接</td>
                    </tr>
                    <tr>
                        <td>📺 B站</td>
                        <td><code>https://b23.tv/xxxxxx</code></td>
                        <td>短链分享</td>
                    </tr>
                </tbody>
            </table>

            <p class="reveal" style="margin-top: clamp(0.6rem, 1.5vh, 1.2rem); font-size: var(--small-size);">
                每次仅限一个链接，不支持批量上传
            </p>
        </div>
    </section>

    <!-- ===========================================
         SLIDE 8: 常见问题
         =========================================== -->
    <section class="slide" data-slide="8">
        <div class="deco-circle deco-circle-2 deco reveal-fade"></div>
        <div class="deco-circle deco-circle-3 deco reveal-fade"></div>
        <div class="vline deco reveal-fade"></div>

        <div class="slide-content" style="align-items: center; text-align: center;">
            <p class="section-num reveal">07</p>
            <h2 class="reveal">常见问题</h2>

            <div class="faq-grid">
                <div class="faq-card reveal-scale">
                    <div class="q">公共 Key 有多少次免费额度？</div>
                    <div class="a">约 10000 次。超出后 API 返回 3107 错误，需配置自己的 Key。</div>
                </div>
                <div class="faq-card reveal-scale">
                    <div class="q">如何获取自己的 API Key？</div>
                    <div class="a">前往 <strong style="color: var(--accent-warm); font-weight: 500;">redfox.hk</strong> 注册获取，格式为 ark_xxx。</div>
                </div>
                <div class="faq-card reveal-scale">
                    <div class="q">下载的视频有水印吗？</div>
                    <div class="a">没有。API 返回的是无水印直链，画质与原始作品一致。</div>
                </div>
                <div class="faq-card reveal-scale">
                    <div class="q">支持图文下载吗？</div>
                    <div class="a">支持图文下载（暂不支持小红书图文）。自动下载所有图片，按序号命名。</div>
                </div>
            </div>
        </div>
    </section>

    <!-- ===========================================
         SLIDE 9: 为什么选择
         =========================================== -->
    <section class="slide" data-slide="9">
        <div class="deco-circle deco-circle-1 deco reveal-fade"></div>
        <div class="deco-circle deco-circle-2 deco reveal-fade"></div>
        <div class="vline deco reveal-fade"></div>

        <div class="slide-content" style="align-items: center; text-align: center;">
            <p class="section-num reveal">08</p>
            <h2 class="reveal">为什么选择</h2>

            <div class="advantage-grid">
                <div class="advantage-card reveal-scale">
                    <span class="icon">🔌</span>
                    <h3>无需抓包</h3>
                    <p>不需要分析网页源码或抓取接口，只需粘贴链接</p>
                </div>
                <div class="advantage-card reveal-scale">
                    <span class="icon">⚡</span>
                    <h3>持续可用</h3>
                    <p>基于稳定 API，不依赖爬虫反爬对抗</p>
                </div>
                <div class="advantage-card reveal-scale">
                    <span class="icon">🚀</span>
                    <h3>开箱即用</h3>
                    <p>内置公共 Key，拿到就能用</p>
                </div>
                <div class="advantage-card reveal-scale">
                    <span class="icon">🔒</span>
                    <h3>隐私安全</h3>
                    <p>API Key 本地存储，安全可靠</p>
                </div>
            </div>
        </div>
    </section>

    <!-- ===========================================
         SLIDE 10: 了解更多 / THANK YOU
         =========================================== -->
    <section class="slide title-slide end-slide" data-slide="10">
        <div class="deco-circle deco-circle-1 deco reveal-fade"></div>
        <div class="deco-circle deco-circle-2 deco reveal-fade"></div>
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        <div class="vline deco reveal-fade"></div>

        <div class="slide-content">
            <h1 class="reveal">了解更多</h1>
            <p class="reveal subtitle">
                本工具基于 redfox.hk 的 parseWork/parse 接口构建
            </p>
            <div class="end-links reveal">
                <a href="https://redfox.hk/settings/api-keys?source=skillhub" target="_blank">redfox.hk →</a>
                <a href="https://skillhub.ai" target="_blank">SkillHub →</a>
                <a href="https://github.com" target="_blank">GitHub →</a>
            </div>
            <p class="reveal meta" style="margin-top: clamp(2rem, 5vh, 4rem);">感谢审阅</p>
        </div>
    </section>

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