/* ==================== CSS Variables - Light Fire Theme ==================== */
:root {
    /* Base colors - light/cream theme */
    --color-bg: #faf8f4;            /* warm cream background */
    --color-bg-pure: #ffffff;        /* pure white surface */
    --color-bg-soft: #f5f0e6;        /* soft cream surface */
    --color-bg-elev: #ffffff;        /* elevated card surface */
    --color-border: #e8e3d8;         /* subtle warm border */
    --color-border-strong: #d4cdba;  /* stronger border */

    /* Text colors - dark on light */
    --color-text-primary: #1a1410;   /* deep brown-black */
    --color-text-secondary: #5a5048; /* warm gray */
    --color-text-muted: #8a8077;     /* lighter warm gray */

    /* Fire gradient (matches logo: yellow → orange → red) */
    --color-fire-1: #ffd54f;         /* bright yellow */
    --color-fire-2: #ffa726;         /* orange */
    --color-fire-3: #ff5722;         /* bright red-orange */
    --color-fire-4: #d84315;         /* deep red */
    --color-fire-5: #bf360c;         /* darkest red */

    --gradient-fire: linear-gradient(135deg, #ffd54f 0%, #ffa726 35%, #ff5722 75%, #d84315 100%);
    --gradient-fire-soft: linear-gradient(135deg, rgba(255, 213, 79, 0.15) 0%, rgba(255, 87, 34, 0.15) 100%);
    --gradient-fire-hover: linear-gradient(135deg, #ffe082 0%, #ffb74d 35%, #ff7043 75%, #e64a19 100%);

    --color-success: #43a047;
    --color-danger: #e53935;

    --shadow-sm: 0 1px 3px rgba(60, 30, 10, 0.08);
    --shadow-md: 0 4px 12px rgba(60, 30, 10, 0.10);
    --shadow-lg: 0 8px 24px rgba(60, 30, 10, 0.12);
    --shadow-glow: 0 4px 20px rgba(255, 87, 34, 0.25);
    --shadow-fire: 0 0 24px rgba(255, 87, 34, 0.35);

    --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);

    --font-display: 'Black Ops One', 'Russo One', 'Orbitron', sans-serif;
    --font-mono: 'Orbitron', 'Russo One', sans-serif;
    --font-body: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
}

/* ==================== Reset ==================== */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
    font-family: var(--font-body);
    background: var(--color-bg);
    color: var(--color-text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
    position: relative;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
a { color: inherit; text-decoration: none; transition: var(--transition); }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
input, textarea { font-family: inherit; color: inherit; background: none; border: none; outline: none; }
img { max-width: 100%; height: auto; display: block; }
::selection { background: var(--color-fire-3); color: white; }

::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: var(--color-bg-soft); }
::-webkit-scrollbar-thumb { background: var(--gradient-fire); border-radius: 5px; }
::-webkit-scrollbar-thumb:hover { background: var(--gradient-fire-hover); }

/* ==================== Background Effects (subtle for light theme) ==================== */
.bg-grid {
    position: fixed; inset: 0; pointer-events: none; z-index: -3;
    background-image:
        linear-gradient(rgba(255, 87, 34, 0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 87, 34, 0.04) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse at center, black 0%, transparent 70%);
    -webkit-mask-image: radial-gradient(ellipse at center, black 0%, transparent 70%);
}
.bg-glow {
    position: fixed; inset: 0; pointer-events: none; z-index: -2;
    background:
        radial-gradient(ellipse 800px 400px at 20% 0%, rgba(255, 213, 79, 0.20) 0%, transparent 60%),
        radial-gradient(ellipse 800px 400px at 80% 100%, rgba(255, 87, 34, 0.15) 0%, transparent 60%);
}

/* ==================== Container ==================== */
.container { max-width: 1280px; margin: 0 auto; padding: 0 24px; }

/* ==================== Navigation ==================== */
.nav {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-border);
    transition: var(--transition);
}
.nav.scrolled { box-shadow: var(--shadow-sm); }
.nav-container {
    max-width: 1280px; margin: 0 auto; padding: 12px 24px;
    display: flex; align-items: center; justify-content: space-between; gap: 24px;
}
.nav-logo { display: flex; align-items: center; gap: 12px; }
.nav-brand { display: flex; align-items: center; }
.logo-img {
    height: 42px; width: auto; display: block;
    filter: drop-shadow(0 2px 6px rgba(255, 87, 34, 0.25));
    transition: var(--transition);
}
.nav-logo:hover .logo-img {
    filter: drop-shadow(0 4px 12px rgba(255, 87, 34, 0.4));
    transform: translateY(-1px);
}
.nav-biu { display: flex; align-items: center; gap: 12px; }
.nav-logo-sep { width: 1px; height: 24px; background: var(--color-border-strong); }
.nav-biu-logo {
    height: 22px; width: auto; display: block;
    transition: var(--transition);
}
.nav-biu:hover .nav-biu-logo { transform: translateY(-1px); }
.nav-links-wrap { display: flex; align-items: center; gap: 20px; }
.nav-links { display: flex; list-style: none; gap: 28px; }
.nav-links a {
    font-size: 14px; font-weight: 600; color: var(--color-text-secondary);
    position: relative; padding: 6px 0;
    letter-spacing: 0.5px;
}
.nav-links a::after {
    content: ''; position: absolute; bottom: 0; left: 0; width: 0; height: 2px;
    background: var(--gradient-fire); transition: width 0.3s;
    border-radius: 2px;
}
.nav-links a:hover { color: var(--color-text-primary); }
.nav-links a:hover::after { width: 100%; }
.nav-cta {
    padding: 10px 22px; background: var(--gradient-fire); color: white;
    font-weight: 700; font-size: 13px; letter-spacing: 1.5px; text-transform: uppercase;
    border-radius: var(--radius-md);
    transition: var(--transition);
}
.nav-cta:hover {
    background: var(--gradient-fire-hover); transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

/* ==================== Hero (Compact) ==================== */
.hero {
    position: relative; padding: 100px 24px 36px; overflow: hidden;
    background: linear-gradient(180deg, var(--color-bg-pure) 0%, var(--color-bg) 100%);
}
.hero-content { position: relative; z-index: 1; text-align: center; max-width: 980px; margin: 0 auto; }
.hero-tag {
    display: inline-flex; align-items: center; gap: 10px; padding: 6px 14px;
    background: var(--gradient-fire-soft); border: 1px solid rgba(255, 87, 34, 0.25);
    border-radius: 20px; font-family: var(--font-mono); font-size: 11px; font-weight: 700;
    color: var(--color-fire-4); letter-spacing: 2px; margin-bottom: 18px;
}
.tag-line { width: 20px; height: 1px; background: var(--color-fire-3); }
.hero-title {
    font-family: var(--font-display); line-height: 1; margin-bottom: 14px;
    display: flex; flex-direction: column; align-items: center; gap: 4px;
}
.title-en {
    font-size: clamp(48px, 9vw, 110px);
    background: var(--gradient-fire); -webkit-background-clip: text; background-clip: text;
    -webkit-text-fill-color: transparent; letter-spacing: 0.04em;
    filter: drop-shadow(0 4px 16px rgba(255, 87, 34, 0.30));
}
.title-cn {
    color: var(--color-text-primary); font-size: clamp(20px, 2.5vw, 28px);
    letter-spacing: 0.3em; margin-top: 4px; font-weight: 700;
}
.hero-subtitle {
    font-size: clamp(14px, 1.5vw, 16px); color: var(--color-text-secondary);
    margin-bottom: 26px; letter-spacing: 3px; font-weight: 500;
}
.hero-stats {
    display: flex; justify-content: center; gap: 0; margin-bottom: 24px;
    background: var(--color-bg-pure); border: 1px solid var(--color-border);
    border-radius: var(--radius-lg); padding: 16px 8px; max-width: 720px; margin-left: auto; margin-right: auto;
    box-shadow: var(--shadow-sm);
}
.stat {
    text-align: center; padding: 0 32px; position: relative; flex: 1;
}
.stat:not(:last-child)::after {
    content: ''; position: absolute; right: 0; top: 50%; transform: translateY(-50%);
    width: 1px; height: 36px; background: var(--color-border);
}
.stat-value {
    font-family: var(--font-display); font-size: clamp(22px, 2.6vw, 30px);
    background: var(--gradient-fire); -webkit-background-clip: text; background-clip: text;
    -webkit-text-fill-color: transparent; letter-spacing: 1px; margin-bottom: 2px;
    line-height: 1.1;
}
.stat-label {
    font-size: 11px; color: var(--color-text-muted); text-transform: uppercase; letter-spacing: 2px;
    font-weight: 600;
}
.hero-buttons { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.btn {
    display: inline-flex; align-items: center; gap: 8px; padding: 12px 26px;
    font-weight: 700; font-size: 13px; letter-spacing: 1.5px; text-transform: uppercase;
    transition: var(--transition); cursor: pointer; position: relative; overflow: hidden;
    border-radius: var(--radius-md);
}
.btn-primary { background: var(--gradient-fire); color: white; }
.btn-primary:hover {
    background: var(--gradient-fire-hover); transform: translateY(-2px); box-shadow: var(--shadow-glow);
}
.btn-secondary {
    background: var(--color-bg-pure); color: var(--color-text-primary);
    border: 1px solid var(--color-border-strong);
}
.btn-secondary:hover {
    border-color: var(--color-fire-3); color: var(--color-fire-4); transform: translateY(-2px);
    background: var(--color-bg-soft);
}
.btn-large { padding: 14px 36px; font-size: 14px; }

/* ==================== Main Content - Two Column Layout ==================== */
.main-content {
    padding: 24px 0 60px;
}
.main-grid {
    display: grid;
    grid-template-columns: 380px 1fr;
    gap: 24px;
    align-items: start;
}
.sidebar {
    position: sticky; top: 80px;
    display: flex; flex-direction: column; gap: 16px;
}
.content-area { min-width: 0; }

/* ==================== Cards ==================== */
.card {
    background: var(--color-bg-pure); border: 1px solid var(--color-border);
    border-radius: var(--radius-lg); overflow: hidden;
    box-shadow: var(--shadow-sm);
}
.card-header {
    padding: 16px 20px; border-bottom: 1px solid var(--color-border);
    background: linear-gradient(90deg, var(--color-bg-soft) 0%, var(--color-bg-pure) 100%);
    display: flex; align-items: center; justify-content: space-between; gap: 12px;
}
.card-header h3 {
    font-family: var(--font-display); font-size: 16px; color: var(--color-text-primary);
    letter-spacing: 1.2px; display: flex; align-items: center; gap: 10px;
}
.card-num {
    font-family: var(--font-mono); font-size: 12px; font-weight: 700;
    color: white; letter-spacing: 1px; padding: 3px 8px;
    background: var(--gradient-fire); border-radius: var(--radius-sm);
}
.card-tag {
    font-size: 10px; padding: 3px 8px;
    background: var(--color-bg-soft); border: 1px solid var(--color-border-strong);
    color: var(--color-text-secondary); letter-spacing: 0.5px; border-radius: var(--radius-sm);
    font-weight: 600;
}
.card-tag.required { background: var(--gradient-fire-soft); border-color: rgba(255, 87, 34, 0.3); color: var(--color-fire-4); }
.card-body { padding: 18px 20px; }

/* ==================== Sidebar - Rules Card ==================== */
.rules-card .card-header { background: linear-gradient(135deg, rgba(255, 213, 79, 0.12) 0%, rgba(255, 87, 34, 0.10) 100%); }
.rules-card .card-body { padding: 16px 20px; }
.rules-list { list-style: none; }
.rules-list li {
    padding: 9px 0; color: var(--color-text-secondary);
    display: flex; gap: 10px; font-size: 13px; line-height: 1.6;
    border-bottom: 1px dashed var(--color-border);
}
.rules-list li:last-child { border-bottom: none; }
.rules-list li strong { color: var(--color-text-primary); font-weight: 700; }
.rules-list li .highlight { color: var(--color-fire-4); font-weight: 700; }
.rules-list .bullet {
    color: var(--color-fire-3); font-weight: bold; flex-shrink: 0; font-size: 14px;
}

/* QQ Group Mini Card */
.qq-mini {
    display: flex; align-items: center; gap: 12px;
    padding: 14px 16px;
    background: linear-gradient(135deg, rgba(255, 213, 79, 0.10) 0%, rgba(255, 87, 34, 0.08) 100%);
    border: 1px solid rgba(255, 87, 34, 0.20);
    border-radius: var(--radius-md);
}
.qq-mini-icon {
    width: 38px; height: 38px; flex-shrink: 0;
    background: var(--gradient-fire); border-radius: 50%;
    display: flex; align-items: center; justify-content: center; color: white;
    box-shadow: 0 2px 8px rgba(255, 87, 34, 0.30);
}
.qq-mini-content { flex: 1; min-width: 0; }
.qq-mini-content h4 { font-size: 13px; color: var(--color-text-primary); font-weight: 700; margin-bottom: 2px; }
.qq-mini-content p { font-size: 11px; color: var(--color-text-muted); }
.qq-mini-content strong { color: var(--color-fire-4); font-weight: 700; }

/* ==================== Registration Form ==================== */
.form-section {
    background: var(--color-bg-pure); border: 1px solid var(--color-border);
    border-radius: var(--radius-lg); margin-bottom: 16px; overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}
.form-section:hover { box-shadow: var(--shadow-md); }
.form-section-header {
    display: flex; align-items: center; gap: 10px;
    padding: 14px 20px; border-bottom: 1px solid var(--color-border);
    background: linear-gradient(90deg, var(--color-bg-soft) 0%, var(--color-bg-pure) 100%);
}
.form-section-header h3 {
    font-family: var(--font-display); font-size: 15px; color: var(--color-text-primary); letter-spacing: 1.2px;
}
.form-body { padding: 18px 20px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-bottom: 14px; }
.form-row:last-child { margin-bottom: 0; }
.form-group { display: flex; flex-direction: column; }
.form-group.full { grid-column: 1 / -1; }
.form-group label {
    font-size: 12px; font-weight: 700; color: var(--color-text-primary);
    margin-bottom: 6px; letter-spacing: 0.5px;
}
.optional-label {
    font-size: 10px; padding: 2px 6px; margin-left: 6px;
    background: var(--color-bg-soft); border: 1px solid var(--color-border);
    color: var(--color-text-muted); letter-spacing: 0.5px; border-radius: var(--radius-sm);
    font-weight: 600;
}
.required { color: var(--color-fire-3); margin-left: 3px; }
.form-group input[type="text"], .form-group textarea {
    width: 100%; padding: 10px 14px; background: var(--color-bg);
    border: 1.5px solid var(--color-border); color: var(--color-text-primary);
    font-size: 14px; transition: var(--transition); border-radius: var(--radius-md);
}
.form-group input[type="text"]:focus, .form-group textarea:focus {
    border-color: var(--color-fire-3); background: var(--color-bg-pure);
    box-shadow: 0 0 0 3px rgba(255, 87, 34, 0.10);
}
.form-group input::placeholder, .form-group textarea::placeholder { color: var(--color-text-muted); }
.form-group input.error, .form-group textarea.error {
    border-color: var(--color-danger); background: rgba(229, 57, 53, 0.04);
}
.form-hint { font-size: 11px; color: var(--color-text-muted); margin-top: 5px; letter-spacing: 0.2px; }
.error-msg { display: none; font-size: 11px; color: var(--color-danger); margin-top: 5px; }
.error-msg.show { display: block; }

/* Logo Upload */
.logo-upload-area {
    display: flex; align-items: center; gap: 16px; padding: 12px;
    background: var(--color-bg-soft); border: 1.5px dashed var(--color-border-strong);
    border-radius: var(--radius-md);
}
.logo-preview {
    width: 80px; height: 80px; background: var(--color-bg-pure);
    border: 1px solid var(--color-border); border-radius: var(--radius-md);
    display: flex; flex-direction: column;
    align-items: center; justify-content: center; color: var(--color-text-muted);
    flex-shrink: 0; overflow: hidden;
}
.logo-preview svg { margin-bottom: 3px; }
.logo-preview p { font-size: 10px; letter-spacing: 0.5px; }
.logo-preview img { width: 100%; height: 100%; object-fit: cover; }
.logo-actions { display: flex; gap: 8px; flex: 1; flex-wrap: wrap; }
.btn-upload, .btn-ai {
    display: inline-flex; align-items: center; gap: 6px; padding: 8px 14px;
    background: var(--color-bg-pure); border: 1px solid var(--color-border-strong);
    color: var(--color-text-primary); font-size: 12px; font-weight: 700;
    letter-spacing: 0.5px; cursor: pointer; transition: var(--transition);
    border-radius: var(--radius-md);
}
.btn-upload:hover {
    border-color: var(--color-fire-3); color: var(--color-fire-4);
    background: var(--color-bg-soft);
}
.btn-ai {
    background: var(--gradient-fire); color: white; border-color: transparent;
}
.btn-ai:hover { background: var(--gradient-fire-hover); box-shadow: var(--shadow-glow); transform: translateY(-1px); }

/* Player Cards */
.player-list { display: flex; flex-direction: column; gap: 10px; }
.player-card {
    background: var(--color-bg); border: 1px solid var(--color-border);
    border-left: 3px solid var(--color-fire-3);
    border-radius: var(--radius-md);
    padding: 12px 14px; transition: var(--transition);
}
.player-card:hover { background: var(--color-bg-soft); }
.player-header {
    display: flex; align-items: center; justify-content: space-between;
    margin-bottom: 8px; padding-bottom: 6px; border-bottom: 1px dashed var(--color-border);
}
.player-tag {
    font-family: var(--font-mono); font-size: 11px; font-weight: 700;
    background: var(--gradient-fire); -webkit-background-clip: text; background-clip: text;
    -webkit-text-fill-color: transparent; letter-spacing: 1.2px;
    text-transform: uppercase;
}
.player-card .form-row { margin-bottom: 0; gap: 12px; }

/* QQ Group Section */
.qq-group-info {
    display: flex; gap: 16px; padding: 6px 4px; align-items: center;
}
.qq-icon-large {
    width: 64px; height: 64px; background: var(--gradient-fire-soft);
    border: 1.5px solid rgba(255, 87, 34, 0.30);
    display: flex; align-items: center; justify-content: center;
    color: var(--color-fire-4); flex-shrink: 0; border-radius: var(--radius-md);
}
.qq-group-content { flex: 1; }
.qq-group-content h4 {
    font-size: 14px; color: var(--color-text-primary);
    margin-bottom: 4px; font-weight: 700;
}
.qq-number {
    font-size: 13px; color: var(--color-text-secondary);
    margin-bottom: 4px; font-weight: 600;
}
.qq-number span {
    background: var(--gradient-fire); -webkit-background-clip: text; background-clip: text;
    -webkit-text-fill-color: transparent; margin-left: 6px; font-weight: 800;
}
.qq-note { color: var(--color-text-secondary); font-size: 11px; margin-bottom: 8px; }
.qq-note strong { color: var(--color-fire-4); }

.checkbox-label {
    display: flex; align-items: flex-start; gap: 10px; cursor: pointer;
    color: var(--color-text-primary); font-size: 13px; line-height: 1.5; user-select: none;
}
.checkbox-label input { position: absolute; opacity: 0; pointer-events: none; }
.checkmark {
    width: 18px; height: 18px; background: var(--color-bg-pure);
    border: 1.5px solid var(--color-border-strong); display: inline-flex;
    align-items: center; justify-content: center; flex-shrink: 0;
    transition: var(--transition); position: relative; margin-top: 1px;
    border-radius: 3px;
}
.checkbox-label input:checked + .checkmark {
    background: var(--gradient-fire); border-color: var(--color-fire-3);
}
.checkbox-label input:checked + .checkmark::after {
    content: ''; position: absolute; left: 5px; top: 1px; width: 5px; height: 10px;
    border: solid white; border-width: 0 2px 2px 0; transform: rotate(45deg);
}
.agreement { padding: 6px 0 14px; }
.form-submit { display: flex; justify-content: center; padding-top: 14px; }

/* ==================== Footer ==================== */
.footer {
    background: var(--color-bg-pure); border-top: 1px solid var(--color-border);
    padding: 24px 0 20px;
}
.footer-content {
    display: flex; align-items: center; justify-content: space-between;
    gap: 16px; flex-wrap: wrap; margin-bottom: 14px;
}
.footer-brand { display: flex; align-items: center; gap: 12px; }
.footer-logo-img {
    height: 36px; width: auto; display: block;
    filter: drop-shadow(0 2px 4px rgba(255, 87, 34, 0.20));
}
.footer-brand p { color: var(--color-text-muted); font-size: 12px; }
.footer-right { color: var(--color-text-secondary); font-size: 13px; }
.footer-right strong {
    background: var(--gradient-fire); -webkit-background-clip: text; background-clip: text;
    -webkit-text-fill-color: transparent; font-weight: 700;
}
.footer-bottom { text-align: center; color: var(--color-text-muted); font-size: 11px; padding-top: 14px; border-top: 1px solid var(--color-border); }

/* ==================== Modal ==================== */
.modal {
    display: none; position: fixed; inset: 0; background: rgba(26, 20, 16, 0.55);
    z-index: 2000; align-items: center; justify-content: center; padding: 20px;
    backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
}
.modal.show { display: flex; animation: fadeIn 0.3s; }
@keyframes fadeIn { from { opacity: 0; transform: scale(0.95); } to { opacity: 1; transform: scale(1); } }
.modal-content {
    background: var(--color-bg-pure); border: 1px solid var(--color-border);
    max-width: 540px; width: 100%; max-height: 90vh; overflow-y: auto;
    border-radius: var(--radius-lg); box-shadow: var(--shadow-lg);
}
.modal-content.modal-small { max-width: 420px; text-align: center; padding: 32px 24px; }
.modal-header {
    display: flex; align-items: center; justify-content: space-between;
    padding: 14px 20px; border-bottom: 1px solid var(--color-border);
    background: linear-gradient(90deg, var(--color-bg-soft) 0%, var(--color-bg-pure) 100%);
}
.modal-header h3 { font-family: var(--font-display); font-size: 16px; color: var(--color-text-primary); letter-spacing: 1px; }
.modal-close {
    width: 28px; height: 28px; background: var(--color-bg-soft);
    border: 1px solid var(--color-border); color: var(--color-text-secondary);
    font-size: 18px; line-height: 1; transition: var(--transition);
    border-radius: var(--radius-sm);
}
.modal-close:hover { background: var(--color-danger); color: white; border-color: var(--color-danger); }
.modal-body { padding: 20px; }
.modal-desc { color: var(--color-text-secondary); font-size: 13px; margin-bottom: 14px; }
.modal .form-group { margin-bottom: 14px; }
.modal .form-group label { font-size: 12px; }

.color-options { display: grid; grid-template-columns: repeat(2, 1fr); gap: 8px; margin-top: 4px; }
.color-option {
    display: flex; align-items: center; gap: 10px; padding: 8px 12px;
    background: var(--color-bg-soft); border: 1.5px solid var(--color-border);
    cursor: pointer; transition: var(--transition); border-radius: var(--radius-md);
}
.color-option:hover { border-color: var(--color-fire-3); }
.color-option input { position: absolute; opacity: 0; pointer-events: none; }
.color-option input:checked + .color-swatch {
    box-shadow: 0 0 0 2px var(--color-fire-3); transform: scale(1.1);
}
.color-swatch {
    width: 22px; height: 22px; display: inline-block; transition: var(--transition);
    border: 1px solid var(--color-border-strong); border-radius: 4px;
}
.color-option span:last-child { color: var(--color-text-primary); font-size: 12px; font-weight: 600; }

.ai-preview {
    margin: 14px 0; padding: 16px; background: var(--color-bg-soft);
    border: 1px solid var(--color-border); min-height: 160px;
    display: flex; align-items: center; justify-content: center;
    border-radius: var(--radius-md);
}
.ai-placeholder { text-align: center; color: var(--color-text-muted); }
.ai-placeholder p { margin-top: 8px; font-size: 13px; }
.ai-preview img { max-width: 100%; max-height: 160px; box-shadow: var(--shadow-md); border-radius: var(--radius-sm); }

.modal-actions { display: flex; gap: 10px; justify-content: flex-end; }
.modal-actions .btn:disabled { opacity: 0.5; cursor: not-allowed; }
.modal-actions .btn-secondary { border: 1px solid var(--color-border-strong); }

/* Success Modal */
.success-icon {
    width: 60px; height: 60px; margin: 0 auto 14px;
    background: rgba(67, 160, 71, 0.12); border: 2px solid var(--color-success);
    border-radius: 50%; display: flex; align-items: center; justify-content: center;
    color: var(--color-success);
}
.modal-small h3 { font-family: var(--font-display); font-size: 20px; color: var(--color-text-primary); margin-bottom: 8px; letter-spacing: 1.2px; }
.modal-small p { color: var(--color-text-secondary); font-size: 13px; margin-bottom: 6px; }
.success-note { color: var(--color-fire-4) !important; font-weight: 600; margin: 8px 0 18px !important; }
.modal-small .btn { margin-top: 8px; }

/* ==================== Responsive ==================== */
@media (max-width: 1024px) {
    .main-grid { grid-template-columns: 1fr; }
    .sidebar { position: static; }
}
@media (max-width: 768px) {
    .container { padding: 0 16px; }
    .hero { padding: 80px 16px 24px; }
    .hero-stats { flex-direction: column; gap: 12px; padding: 14px; }
    .stat { padding: 6px 0; }
    .stat:not(:last-child)::after { display: none; }
    .stat:not(:last-child) { border-bottom: 1px solid var(--color-border); }
    .form-row { grid-template-columns: 1fr; }
    .form-body { padding: 14px 16px; }
    .form-section-header { padding: 12px 16px; }
    .form-section-header h3 { font-size: 14px; }
    .qq-group-info { flex-direction: column; text-align: center; }
    .nav-links { display: none; }
    .nav-container { padding: 10px 16px; }
    .nav-cta { padding: 8px 14px; font-size: 12px; }
    .logo-actions { width: 100%; }
    .btn-upload, .btn-ai { flex: 1; justify-content: center; }
    .color-options { grid-template-columns: 1fr; }
    .footer-content { flex-direction: column; text-align: center; }
    .logo-img { height: 34px; }
    .footer-logo-img { height: 30px; }
    .main-content { padding: 16px 0 40px; }
}
@media (max-width: 480px) {
    .player-card .form-row { grid-template-columns: 1fr; }
    .logo-upload-area { flex-direction: column; }
    .hero-title { gap: 2px; }
    .title-cn { letter-spacing: 0.2em; }
    .nav-biu { display: none; }
}

/* ==================== Biubiu Sponsor Elements ==================== */
/* Footer sponsor line */
.footer-sponsor {
    display: flex; align-items: center; justify-content: center;
    flex-wrap: wrap; gap: 10px;
    padding: 14px 18px;
    margin: 16px 0 18px;
    background: rgba(0, 170, 255, 0.04);
    border: 1px dashed rgba(0, 170, 255, 0.28);
    border-radius: 4px;
    font-size: 12px;
    color: var(--color-text-secondary);
    letter-spacing: 0.3px;
}
.footer-sponsor .sponsor-label {
    color: var(--color-text-muted);
    font-size: 11px;
    letter-spacing: 1px;
}
.footer-sponsor .sponsor-brand {
    display: inline-flex; align-items: center; gap: 6px;
    color: var(--color-text-primary);
}
.footer-sponsor .sponsor-brand strong {
    font-weight: 700;
    background: linear-gradient(135deg, #00aaff 0%, #1C92F1 100%);
    -webkit-background-clip: text; background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: 0.5px;
}
.footer-sponsor .biubiu-logo {
    height: 16px; width: auto;
    filter: drop-shadow(0 0 4px rgba(0, 170, 255, 0.4));
    flex-shrink: 0;
}
.footer-sponsor .sponsor-biu-logo {
    height: 30px; width: auto; display: block; flex-shrink: 0;
}
.footer-sponsor .sponsor-sep {
    color: #00aaff; font-weight: 700; font-size: 13px;
    opacity: 0.7; margin: 0 -2px;
}
.footer-sponsor .sponsor-divider {
    color: var(--color-text-dim); opacity: 0.5; font-size: 11px;
    margin: 0 4px;
}

/* Network Guarantee Card (left sidebar) */
.guarantee-card {
    display: flex; flex-direction: column; gap: 12px;
    padding: 14px 16px;
    background: linear-gradient(135deg, rgba(0, 170, 255, 0.10) 0%, rgba(0, 170, 255, 0.03) 100%);
    border: 1px solid rgba(0, 170, 255, 0.28);
    border-radius: 6px;
    position: relative;
    box-shadow: 0 4px 14px rgba(0, 170, 255, 0.12);
}
.guarantee-card::before {
    content: ''; position: absolute;
    top: 0; left: 0; right: 0; height: 2px;
    background: linear-gradient(90deg, transparent, #00aaff, transparent);
    opacity: 0.7;
}
.guarantee-header {
    display: flex; align-items: center; gap: 10px;
    padding-bottom: 10px;
    border-bottom: 1px dashed rgba(0, 170, 255, 0.25);
}
.guarantee-avatar {
    width: 42px; height: 42px; flex-shrink: 0;
    border-radius: 10px; display: block;
    box-shadow: 0 2px 8px rgba(0, 170, 255, 0.35);
}
.guarantee-kv {
    width: 100%; display: block; border-radius: 8px;
    border: 1px solid rgba(0, 170, 255, 0.25);
}
.guarantee-title { display: flex; flex-direction: column; line-height: 1.25; }
.guarantee-title strong {
    font-size: 13.5px; font-weight: 700;
    color: var(--color-text-primary);
    letter-spacing: 1.2px;
}
.guarantee-title span {
    font-size: 10.5px;
    color: var(--color-text-muted);
    letter-spacing: 0.5px;
    margin-top: 2px;
}
.guarantee-title span strong,
.guarantee-title span b {
    background: linear-gradient(135deg, #00aaff 0%, #1C92F1 100%);
    -webkit-background-clip: text; background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 700;
}
.guarantee-list { list-style: none; display: flex; flex-direction: column; gap: 8px; }
.guarantee-list li {
    display: flex; gap: 8px;
    font-size: 11.5px; line-height: 1.5;
    color: var(--color-text-secondary);
}
.guarantee-list li strong { color: var(--color-text-primary); font-weight: 600; }
.guarantee-list .g-bullet {
    color: #00aaff;
    font-weight: 700; flex-shrink: 0;
    margin-top: 1px;
}
.guarantee-footer {
    margin-top: 2px; padding-top: 10px;
    border-top: 1px dashed rgba(0, 170, 255, 0.2);
    font-size: 11.5px;
    text-align: center;
    color: var(--color-text-secondary);
    font-style: italic;
    letter-spacing: 1px;
}
.guarantee-footer::before,
.guarantee-footer::after { content: '— '; color: #00aaff; opacity: 0.6; }
.guarantee-footer::after { content: ' —'; }

/* Success Modal biubiu benefit line */
.success-benefit {
    display: flex; align-items: center; gap: 10px;
    margin-top: 14px;
    padding: 12px 14px;
    background: linear-gradient(135deg, rgba(0, 170, 255, 0.10) 0%, rgba(0, 170, 255, 0.04) 100%);
    border: 1px solid rgba(0, 170, 255, 0.35);
    border-radius: 6px;
    font-size: 13px; line-height: 1.5;
    color: var(--color-text-secondary);
    text-align: left;
}
.success-benefit .biubiu-mini {
    height: 22px; width: auto; flex-shrink: 0;
    filter: drop-shadow(0 0 5px rgba(0, 170, 255, 0.5));
}
.success-benefit strong { color: var(--color-text-primary); font-weight: 700; }
.success-benefit strong + b,
.success-benefit strong ~ b {
    background: linear-gradient(135deg, #00aaff 0%, #1C92F1 100%);
    -webkit-background-clip: text; background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 700;
}

/* Mobile responsive */
@media (max-width: 768px) {
    .footer-sponsor { font-size: 11px; gap: 6px; padding: 10px 12px; }
    .guarantee-card { padding: 12px 14px; }
    .guarantee-list li { font-size: 11px; }
    .success-benefit { font-size: 12px; padding: 10px 12px; }
}