/* ═══════════════════════════════════════
   ADG PDF Tools — 深色主題 + 彩色磁貼 v2
   強化 UI/UX: Toast、RWD、動畫、互動裁切
   ═══════════════════════════════════════ */

:root {
    --bg-primary: #0a0e1a;
    --bg-secondary: #111827;
    --bg-card: #1a1f35;
    --bg-card-hover: #232942;
    --text-primary: #f0f4ff;
    --text-secondary: #8892b0;
    --text-muted: #5a6380;
    --accent-blue: #3b82f6;
    --accent-cyan: #06b6d4;
    --accent-purple: #8b5cf6;
    --accent-pink: #ec4899;
    --cat-convert-from: #3b82f6;
    --cat-convert-to: #10b981;
    --cat-tools: #f59e0b;
    --cat-image: #ec4899;
    --cat-ai: #8b5cf6;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --shadow-card: 0 4px 24px rgba(0,0,0,0.3);
    --shadow-hover: 0 8px 40px rgba(0,0,0,0.5);
    --shadow-glow: 0 0 30px rgba(59,130,246,0.15);
}

.light-theme {
    --bg-primary: #f8fafc;
    --bg-secondary: #e2e8f0;
    --bg-card: #ffffff;
    --bg-card-hover: #f1f5f9;
    --text-primary: #1e293b;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    --shadow-card: 0 4px 24px rgba(0,0,0,0.05);
    --shadow-hover: 0 8px 40px rgba(0,0,0,0.1);
    --shadow-glow: 0 0 30px rgba(59,130,246,0.15);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: system-ui,-apple-system, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
}

/* ═══ 背景效果 ═══ */
.bg-grid {
    position: fixed; inset: 0; z-index: 0;
    background-image:
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(59,130,246,0.08), transparent),
        radial-gradient(ellipse 60% 40% at 80% 80%, rgba(139,92,246,0.05), transparent);
    pointer-events: none;
}

/* ═══ 頂部導航 ═══ */
.top-nav {
    position: sticky; top: 0; z-index: 100;
    display: flex; align-items: center; justify-content: space-between;
    padding: 1rem 2rem;
    background: rgba(10,14,26,0.85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255,255,255,0.05);
}
.nav-brand {
    display: flex; align-items: center; gap: 0.75rem;
    text-decoration: none; color: var(--text-primary);
}
.nav-brand svg { width: 28px; height: 28px; fill: var(--accent-blue); }
.nav-brand-text {
    font-size: 1.25rem; font-weight: 700;
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-cyan));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.nav-brand-sub {
    font-size: 0.7rem; color: var(--text-muted);
    letter-spacing: 2px; text-transform: uppercase;
}
.nav-links { display: flex; gap: 0.5rem; align-items: center; }
.nav-link {
    padding: 0.5rem 1rem; border-radius: var(--radius-sm);
    color: var(--text-secondary); text-decoration: none;
    font-size: 0.85rem; font-weight: 500;
    transition: all 0.2s;
    border: 1px solid transparent;
}
.nav-link:hover { color: var(--text-primary); background: rgba(255,255,255,0.05); border-color: rgba(255,255,255,0.08); }
.nav-link.active { color: var(--accent-blue); background: rgba(59,130,246,0.1); border-color: rgba(59,130,246,0.2); }

/* ═══ Hero ═══ */
.hero { position: relative; z-index: 1; text-align: center; padding: 4rem 2rem 2rem; }
.hero h1 { font-size: 3rem; font-weight: 800; line-height: 1.2; margin-bottom: 1rem; }
.hero h1 .gradient {
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-cyan), var(--accent-purple));
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-size: 200% 200%;
    animation: gradientShift 3s ease infinite;
}
.hero-desc { font-size: 1.1rem; color: var(--text-secondary); max-width: 600px; margin: 0 auto 2rem; line-height: 1.7; }
.hero-badges { display: flex; justify-content: center; gap: 1rem; flex-wrap: wrap; }
.badge {
    display: flex; align-items: center; gap: 0.4rem;
    padding: 0.4rem 1rem; border-radius: 20px;
    font-size: 0.8rem; font-weight: 500;
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.08);
    color: var(--text-secondary);
    transition: all 0.3s;
}
.badge:hover { background: rgba(255,255,255,0.08); transform: translateY(-1px); }
.badge i { font-size: 0.75rem; color: var(--accent-cyan); }

/* ═══ 分類 Tab ═══ */
.category-tabs {
    position: relative; z-index: 1;
    display: flex; justify-content: center; gap: 0.5rem;
    padding: 1.5rem 2rem; flex-wrap: wrap;
}
.cat-tab {
    padding: 0.6rem 1.2rem; border-radius: 10px;
    border: 1px solid rgba(255,255,255,0.08);
    background: rgba(255,255,255,0.03);
    color: var(--text-secondary);
    font-size: 0.85rem; font-weight: 500;
    cursor: pointer; transition: all 0.3s;
    display: flex; align-items: center; gap: 0.5rem;
}
.cat-tab:hover { background: rgba(255,255,255,0.06); border-color: rgba(255,255,255,0.12); color: var(--text-primary); }
.cat-tab.active { background: rgba(59,130,246,0.12); border-color: rgba(59,130,246,0.3); color: var(--accent-blue); }
.cat-tab .count { background: rgba(255,255,255,0.08); padding: 0.1rem 0.5rem; border-radius: 10px; font-size: 0.7rem; }
.cat-tab.active .count { background: rgba(59,130,246,0.2); }

/* ═══ 工具網格 ═══ */
.tools-section { position: relative; z-index: 1; max-width: 1200px; margin: 0 auto; padding: 1rem 2rem 4rem; }
.section-title {
    font-size: 1.1rem; font-weight: 600; color: var(--text-secondary);
    margin-bottom: 1.5rem; padding-left: 0.5rem;
    display: flex; align-items: center; gap: 0.5rem;
}
.section-title::before { content: ''; width: 3px; height: 1.2rem; border-radius: 2px; }
.section-title[data-cat="convert-from"]::before { background: var(--cat-convert-from); }
.section-title[data-cat="convert-to"]::before { background: var(--cat-convert-to); }
.section-title[data-cat="tools"]::before { background: var(--cat-tools); }
.section-title[data-cat="image"]::before { background: var(--cat-image); }
.section-title[data-cat="ai"]::before { background: var(--cat-ai); }
.tools-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 1rem; margin-bottom: 3rem; }

/* ═══ 工具卡片 ═══ */
.tool-card {
    position: relative; background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 1.5rem; cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid rgba(255,255,255,0.05);
    text-decoration: none; display: flex; flex-direction: column; overflow: hidden;
}
.tool-card::before {
    content: ''; position: absolute; top: 0; left: 0; right: 0;
    height: 3px; border-radius: var(--radius-lg) var(--radius-lg) 0 0; transition: height 0.3s;
}
.tool-card[data-cat="convert-from"]::before { background: var(--cat-convert-from); }
.tool-card[data-cat="convert-to"]::before { background: var(--cat-convert-to); }
.tool-card[data-cat="tools"]::before { background: var(--cat-tools); }
.tool-card[data-cat="image"]::before { background: var(--cat-image); }
.tool-card[data-cat="ai"]::before { background: var(--cat-ai); }
.tool-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); border-color: rgba(255,255,255,0.1); }
.tool-card:hover::before { height: 4px; }
.tool-icon {
    width: 48px; height: 48px; border-radius: var(--radius-md);
    display: flex; align-items: center; justify-content: center;
    font-size: 1.4rem; margin-bottom: 1rem; transition: transform 0.3s;
}
.tool-card:hover .tool-icon { transform: scale(1.1); }
.tool-icon[data-cat="convert-from"] { background: rgba(59,130,246,0.12); color: var(--cat-convert-from); }
.tool-icon[data-cat="convert-to"] { background: rgba(16,185,129,0.12); color: var(--cat-convert-to); }
.tool-icon[data-cat="tools"] { background: rgba(245,158,11,0.12); color: var(--cat-tools); }
.tool-icon[data-cat="image"] { background: rgba(236,72,153,0.12); color: var(--cat-image); }
.tool-icon[data-cat="ai"] { background: rgba(139,92,246,0.12); color: var(--cat-ai); }
.tool-icon[data-cat="extra"] { background: rgba(139,92,246,0.12); color: var(--accent-purple); }
.tool-card[data-cat="extra"]::before { background: var(--accent-purple); }
.section-title[data-cat="extra"]::before { background: var(--accent-purple); }
.tool-name { font-size: 0.95rem; font-weight: 600; color: var(--text-primary); margin-bottom: 0.4rem; }
.tool-desc { font-size: 0.78rem; color: var(--text-muted); line-height: 1.5; }
.tool-badge-wasm {
    position: absolute; top: 12px; right: 12px;
    font-size: 0.6rem; font-weight: 600;
    padding: 0.15rem 0.5rem; border-radius: 6px;
    background: rgba(16,185,129,0.15); color: #10b981; letter-spacing: 0.5px;
}

/* ═══ 工具頁面 ═══ */
.tool-page { display: none; position: relative; z-index: 1; }
.tool-page.active { display: block; animation: fadeIn 0.4s ease; }
.tool-header { text-align: center; padding: 3rem 2rem 1.5rem; }
.tool-header h1 { font-size: 2rem; font-weight: 700; margin-bottom: 0.5rem; }
.tool-header p { color: var(--text-secondary); font-size: 1rem; }
.tool-workspace { max-width: 800px; margin: 0 auto; padding: 0 2rem 4rem; }

/* 上傳區 */
.upload-zone {
    border: 2px dashed rgba(59,130,246,0.3); border-radius: var(--radius-xl);
    padding: 4rem 2rem; text-align: center;
    background: rgba(59,130,246,0.03); cursor: pointer;
    transition: all 0.3s; position: relative;
}
.upload-zone:hover, .upload-zone.dragover {
    border-color: var(--accent-blue);
    background: rgba(59,130,246,0.06);
    box-shadow: 0 0 40px rgba(59,130,246,0.1);
}
.upload-zone.dragover { animation: pulse 1s infinite; }
.upload-zone .icon { font-size: 3rem; color: var(--accent-blue); margin-bottom: 1rem; opacity: 0.7; transition: all 0.3s; }
.upload-zone:hover .icon { opacity: 1; transform: translateY(-5px); }
.upload-zone h3 { font-size: 1.2rem; font-weight: 600; margin-bottom: 0.5rem; }
.upload-zone p { color: var(--text-muted); font-size: 0.85rem; margin-bottom: 1.5rem; }
.btn-upload {
    display: inline-flex; align-items: center; gap: 0.5rem;
    padding: 0.8rem 2rem; border-radius: 12px;
    background: linear-gradient(135deg, var(--accent-blue), #2563eb);
    color: #fff; font-weight: 600; font-size: 0.95rem;
    border: none; cursor: pointer; transition: all 0.3s;
    box-shadow: 0 4px 20px rgba(59,130,246,0.3);
}
.btn-upload:hover { transform: translateY(-2px); box-shadow: 0 6px 30px rgba(59,130,246,0.4); }

/* 檔案列表 */
.file-list { margin-top: 1.5rem; }
.file-item {
    display: flex; align-items: center; gap: 1rem;
    padding: 1rem 1.5rem; background: var(--bg-card);
    border-radius: var(--radius-md); margin-bottom: 0.5rem;
    border: 1px solid rgba(255,255,255,0.05);
    animation: slideIn 0.3s ease;
    transition: all 0.2s;
}
.file-item:hover { border-color: rgba(255,255,255,0.1); background: var(--bg-card-hover); }
.file-item .file-icon {
    width: 40px; height: 40px; border-radius: 10px; flex-shrink: 0;
    background: rgba(239,68,68,0.1); color: #ef4444;
    display: flex; align-items: center; justify-content: center; font-size: 1.1rem;
}
.file-item .file-info { flex: 1; min-width: 0; }
.file-item .file-name { font-size: 0.9rem; font-weight: 500; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.file-item .file-size { font-size: 0.75rem; color: var(--text-muted); }
.file-item .file-remove {
    width: 32px; height: 32px; border-radius: 8px; flex-shrink: 0;
    border: none; cursor: pointer;
    background: rgba(239,68,68,0.1); color: #ef4444;
    display: flex; align-items: center; justify-content: center; transition: all 0.2s;
}
.file-item .file-remove:hover { background: rgba(239,68,68,0.2); transform: scale(1.1); }

/* 處理按鈕 */
.action-bar { display: flex; justify-content: center; gap: 1rem; margin-top: 2rem; }
.btn-process {
    display: inline-flex; align-items: center; gap: 0.6rem;
    padding: 1rem 3rem; border-radius: 14px;
    background: linear-gradient(135deg, #10b981, #059669);
    color: #fff; font-weight: 700; font-size: 1.05rem;
    border: none; cursor: pointer; transition: all 0.3s;
    box-shadow: 0 4px 20px rgba(16,185,129,0.3);
    position: relative; overflow: hidden;
}
.btn-process::after {
    content: ''; position: absolute; inset: 0;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.1), transparent);
    transform: translateX(-100%);
}
.btn-process:hover { transform: translateY(-2px); box-shadow: 0 6px 30px rgba(16,185,129,0.4); }
.btn-process:hover::after { transform: translateX(100%); transition: transform 0.6s; }
.btn-process:disabled { opacity: 0.5; cursor: not-allowed; transform: none; box-shadow: none; }

/* 實時預覽 Layout */
.options-preview-container {
    display: flex; gap: 24px; align-items: flex-start;
    margin: 20px 0;
}
.options-preview-container .options-panel {
    flex: 1; margin: 0; min-width: 300px;
}
.preview-panel {
    flex: 1; min-width: 300px; background: var(--bg-card);
    border: 1px solid rgba(255,255,255,0.08); border-radius: 16px;
    padding: 20px; text-align: center; position: relative;
    box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    min-height: 400px;
}
.preview-panel canvas {
    max-width: 100%; max-height: 500px; border: 1px solid rgba(255,255,255,0.2);
    border-radius: 8px; box-shadow: 0 2px 10px rgba(0,0,0,0.5);
    background: #fff;
}
.preview-title {
    font-size: 0.9rem; font-weight: 600; color: var(--text-secondary);
    margin-bottom: 12px; display: flex; align-items: center; justify-content: space-between;
    width: 100%;
}
@media (max-width: 768px) {
    .options-preview-container { flex-direction: column; }
    .options-preview-container .options-panel, .preview-panel { width: 100%; }
}

/* 進度條 — 強化版 */
.progress-bar {
    width: 100%; height: 6px;
    background: rgba(255,255,255,0.05);
    border-radius: 3px; margin-top: 2rem;
    overflow: hidden; display: none;
}
.progress-bar.active { display: block; }
.progress-fill {
    height: 100%; border-radius: 3px;
    background: linear-gradient(90deg, var(--accent-blue), var(--accent-cyan), var(--accent-purple));
    background-size: 200% 100%;
    transition: width 0.4s ease;
    animation: progressShine 2s linear infinite;
}
.progress-text {
    font-size: 0.8rem; color: var(--text-secondary);
    text-align: center; margin-top: 0.5rem;
    display: none;
}
.progress-bar.active + .progress-text { display: block; }

/* 下載區 */
.download-zone {
    text-align: center; padding: 3rem;
    background: rgba(16,185,129,0.05);
    border: 1px solid rgba(16,185,129,0.15);
    border-radius: var(--radius-xl);
    margin-top: 2rem; display: none;
}
.download-zone.active { display: block; animation: scaleIn 0.5s ease; }
.download-zone .success-icon { font-size: 3.5rem; color: #10b981; margin-bottom: 1rem; animation: bounceIn 0.6s ease; }
.btn-download {
    display: inline-flex; align-items: center; gap: 0.6rem;
    padding: 1rem 2.5rem; border-radius: 14px;
    background: linear-gradient(135deg, var(--accent-blue), #2563eb);
    color: #fff; font-weight: 600; font-size: 1rem;
    border: none; cursor: pointer; transition: all 0.3s;
    box-shadow: 0 4px 20px rgba(59,130,246,0.3); margin-top: 1rem;
}
.btn-download:hover { transform: translateY(-2px); box-shadow: 0 6px 30px rgba(59,130,246,0.4); }
.btn-reset {
    display: inline-flex; align-items: center; gap: 0.5rem;
    padding: 0.6rem 1.5rem; border-radius: 10px;
    background: transparent; border: 1px solid rgba(255,255,255,0.1);
    color: var(--text-secondary); font-size: 0.85rem;
    cursor: pointer; margin-top: 1rem; transition: all 0.2s;
}
.btn-reset:hover { border-color: rgba(255,255,255,0.2); color: var(--text-primary); }

/* ═══ 選項面板 ═══ */
.options-panel {
    background: var(--bg-card); border-radius: var(--radius-lg);
    padding: 1.5rem; margin-top: 1.5rem;
    border: 1px solid rgba(255,255,255,0.05);
    animation: slideIn 0.3s ease;
}
.options-panel h3 {
    font-size: 0.9rem; font-weight: 600; color: var(--text-secondary);
    margin-bottom: 1rem; display: flex; align-items: center; gap: 0.5rem;
}
.option-row { display: flex; align-items: center; gap: 1rem; margin-bottom: 0.75rem; }
.option-label { font-size: 0.85rem; color: var(--text-secondary); min-width: 80px; flex-shrink: 0; }
.option-select, .option-input {
    flex: 1; padding: 0.6rem 1rem; border-radius: var(--radius-sm);
    background: var(--bg-secondary); border: 1px solid rgba(255,255,255,0.08);
    color: var(--text-primary); font-size: 0.85rem; outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
}
.option-select:focus, .option-input:focus {
    border-color: var(--accent-blue);
    box-shadow: 0 0 0 3px rgba(59,130,246,0.1);
}

/* ═══ Toast 通知系統 ═══ */
.toast-container {
    position: fixed; top: 80px; right: 20px; z-index: 9999;
    display: flex; flex-direction: column; gap: 10px;
    pointer-events: none;
    max-width: 420px;
}
.toast {
    display: flex; align-items: flex-start; gap: 12px;
    padding: 14px 18px; border-radius: 14px;
    background: rgba(26,31,53,0.95);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255,255,255,0.08);
    box-shadow: 0 8px 32px rgba(0,0,0,0.4);
    animation: toastIn 0.4s cubic-bezier(0.22, 1, 0.36, 1);
    pointer-events: auto;
    min-width: 300px;
}
.toast.hiding { animation: toastOut 0.3s ease forwards; }
.toast-icon {
    width: 32px; height: 32px; border-radius: 8px; flex-shrink: 0;
    display: flex; align-items: center; justify-content: center;
    font-size: 0.9rem;
}
.toast-content { flex: 1; min-width: 0; }
.toast-title { font-size: 0.85rem; font-weight: 600; margin-bottom: 2px; }
.toast-message { font-size: 0.78rem; color: var(--text-secondary); line-height: 1.4; }
.toast-close {
    width: 24px; height: 24px; border-radius: 6px; flex-shrink: 0;
    border: none; cursor: pointer;
    background: rgba(255,255,255,0.05); color: var(--text-muted);
    display: flex; align-items: center; justify-content: center;
    font-size: 0.7rem; transition: all 0.2s;
}
.toast-close:hover { background: rgba(255,255,255,0.1); color: var(--text-primary); }
.toast-progress {
    position: absolute; bottom: 0; left: 0; right: 0; height: 3px;
    border-radius: 0 0 14px 14px; overflow: hidden;
}
.toast-progress-fill {
    height: 100%; width: 100%;
    transition: width linear;
}

/* Toast 類型 */
.toast.success .toast-icon { background: rgba(16,185,129,0.15); color: #10b981; }
.toast.success .toast-progress-fill { background: #10b981; }
.toast.error .toast-icon { background: rgba(239,68,68,0.15); color: #ef4444; }
.toast.error .toast-progress-fill { background: #ef4444; }
.toast.warning .toast-icon { background: rgba(245,158,11,0.15); color: #f59e0b; }
.toast.warning .toast-progress-fill { background: #f59e0b; }
.toast.info .toast-icon { background: rgba(59,130,246,0.15); color: #3b82f6; }
.toast.info .toast-progress-fill { background: #3b82f6; }
.toast.processing .toast-icon { background: rgba(139,92,246,0.15); color: #8b5cf6; }
.toast.processing .toast-progress-fill { background: linear-gradient(90deg, #8b5cf6, #06b6d4); }

/* ═══ 互動裁切 UI ═══ */
.crop-container {
    position: relative; display: inline-block;
    margin-top: 12px; border-radius: 8px; overflow: hidden;
    cursor: crosshair; user-select: none; touch-action: none;
    max-width: 100%;
}
.crop-container img { display: block; max-width: 100%; height: auto; }
.crop-overlay {
    position: absolute; inset: 0;
    background: rgba(0,0,0,0.5);
    pointer-events: none;
}
.crop-selection {
    position: absolute;
    border: 2px solid var(--accent-blue);
    box-shadow: 0 0 0 9999px rgba(0,0,0,0.5);
    cursor: move;
}
.crop-selection::before {
    content: ''; position: absolute; inset: -1px;
    border: 1px dashed rgba(255,255,255,0.5);
}
.crop-handle {
    position: absolute; width: 10px; height: 10px;
    background: var(--accent-blue); border: 2px solid #fff;
    border-radius: 2px;
}
.crop-handle.tl { top: -5px; left: -5px; cursor: nw-resize; }
.crop-handle.tr { top: -5px; right: -5px; cursor: ne-resize; }
.crop-handle.bl { bottom: -5px; left: -5px; cursor: sw-resize; }
.crop-handle.br { bottom: -5px; right: -5px; cursor: se-resize; }
.crop-info {
    position: absolute; top: 8px; left: 8px;
    background: rgba(0,0,0,0.75); backdrop-filter: blur(4px);
    padding: 4px 8px; border-radius: 6px;
    font-size: 0.7rem; color: #fff;
    pointer-events: none;
}

/* ═══ 簽章拖拽定位 ═══ */
.sign-preview-container {
    position: relative; display: inline-block;
    margin: 12px auto; border-radius: 8px; overflow: hidden;
    background: #fff;
}
.sign-preview-container img { display: block; max-width: 100%; height: auto; }
.sign-draggable {
    position: absolute; cursor: grab; user-select: none; touch-action: none;
    border: 2px dashed rgba(59,130,246,0.5); border-radius: 4px;
    padding: 4px; background: rgba(255,255,255,0.1);
    transition: border-color 0.2s;
}
.sign-draggable:hover { border-color: var(--accent-blue); }
.sign-draggable.dragging { cursor: grabbing; border-color: var(--accent-cyan); }
.sign-draggable img { display: block; width: 100%; height: auto; pointer-events: none; }

/* ═══ 檔案預覽縮圖 ═══ */
.file-thumbnail {
    width: 40px; height: 40px; border-radius: 8px; flex-shrink: 0;
    object-fit: cover; background: var(--bg-secondary);
    border: 1px solid rgba(255,255,255,0.05);
}

/* ═══ 步驟進度指示 ═══ */
.step-indicator {
    display: flex; justify-content: center; gap: 0.5rem;
    margin: 1.5rem 0; padding: 0 1rem;
}
.step-dot {
    width: 8px; height: 8px; border-radius: 50%;
    background: rgba(255,255,255,0.1);
    transition: all 0.3s;
}
.step-dot.active { background: var(--accent-blue); transform: scale(1.3); }
.step-dot.done { background: #10b981; }

/* ═══ Footer ═══ */
.pdf-footer {
    position: relative; z-index: 1;
    text-align: center; padding: 2rem;
    border-top: 1px solid rgba(255,255,255,0.05);
    color: var(--text-muted); font-size: 0.8rem;
}
.pdf-footer a { color: var(--accent-blue); text-decoration: none; }

/* ═══ 動畫 ═══ */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes slideIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes scaleIn {
    from { opacity: 0; transform: scale(0.9); }
    to { opacity: 1; transform: scale(1); }
}
@keyframes bounceIn {
    0% { transform: scale(0); }
    50% { transform: scale(1.2); }
    100% { transform: scale(1); }
}
@keyframes progressShine {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}
@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}
@keyframes pulse {
    0%, 100% { box-shadow: 0 0 0 0 rgba(59,130,246,0.15); }
    50% { box-shadow: 0 0 0 15px rgba(59,130,246,0); }
}
@keyframes toastIn {
    from { opacity: 0; transform: translateX(80px) scale(0.95); }
    to { opacity: 1; transform: translateX(0) scale(1); }
}
@keyframes toastOut {
    from { opacity: 1; transform: translateX(0) scale(1); }
    to { opacity: 0; transform: translateX(80px) scale(0.95); }
}
@keyframes spin { to { transform: rotate(360deg); } }
.fa-spin { animation: spin 1s linear infinite; }

/* ═══ 響應式 — 全面強化 ═══ */
@media (max-width: 1024px) {
    .tools-grid { grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); }
}
@media (max-width: 768px) {
    .hero { padding: 2.5rem 1.5rem 1.5rem; }
    .hero h1 { font-size: 2rem; }
    .hero-desc { font-size: 0.95rem; }
    .tools-section { padding: 1rem 1rem 3rem; }
    .tools-grid { grid-template-columns: repeat(2, 1fr); gap: 0.75rem; }
    .tool-card { padding: 1.2rem; }
    .tool-icon { width: 40px; height: 40px; font-size: 1.1rem; }
    .tool-name { font-size: 0.85rem; }
    .tool-desc { font-size: 0.7rem; }
    .top-nav { padding: 0.8rem 1rem; }
    .nav-brand-text { font-size: 1.05rem; }
    .nav-brand-sub { font-size: 0.6rem; }
    .nav-links .nav-link:not(.active) span { display: none; }
    .category-tabs { padding: 1rem 0.5rem; gap: 0.4rem; }
    .cat-tab { padding: 0.5rem 0.8rem; font-size: 0.78rem; }
    .cat-tab i { display: none; }
    .upload-zone { padding: 2.5rem 1.5rem; }
    .upload-zone .icon { font-size: 2.5rem; }
    .tool-header { padding: 2rem 1rem 1rem; }
    .tool-header h1 { font-size: 1.6rem; }
    .tool-workspace { padding: 0 1rem 3rem; }
    .btn-process { padding: 0.85rem 2rem; font-size: 0.95rem; }
    .btn-download { padding: 0.85rem 2rem; font-size: 0.95rem; }
    .options-panel { padding: 1.2rem; }
    .option-row { flex-direction: column; align-items: stretch; gap: 0.4rem; }
    .option-label { min-width: auto; }
    .toast-container { right: 10px; left: 10px; max-width: 100%; }
    .toast { min-width: auto; }
    .download-zone { padding: 2rem 1.5rem; }
    .hero-badges { gap: 0.5rem; }
    .badge { font-size: 0.72rem; padding: 0.3rem 0.75rem; }
}
@media (max-width: 480px) {
    .tools-grid { grid-template-columns: repeat(2, 1fr); gap: 0.5rem; }
    .tool-card { padding: 1rem; }
    .hero h1 { font-size: 1.6rem; }
    .hero { padding: 2rem 1rem 1rem; }
    .nav-links { gap: 0.3rem; }
    .btn-upload { padding: 0.7rem 1.5rem; font-size: 0.85rem; }
    .file-item { padding: 0.8rem 1rem; gap: 0.75rem; }
    .file-item .file-icon { width: 32px; height: 32px; font-size: 0.9rem; }
}
@media (max-width: 360px) {
    .hero h1 { font-size: 1.4rem; }
    .tool-card { padding: 0.8rem; }
    .tool-name { font-size: 0.8rem; }
}