/* ==========================================================================
   StanThat - Premium High-End Infographic Intro Page Stylesheet
   Luxury Dark Aesthetic with Ambient Glows, Glassmorphism & Sleek Micro-interactions
   ========================================================================== */

.intro {
    /* Premium Color Palette */
    --i-gold: #f5b800;
    --i-gold-bright: #ffe885;
    --i-gold-deep: #c47f00;
    --i-gold-glow: rgba(245, 184, 0, 0.28);
    --i-gold-subtle: rgba(245, 184, 0, 0.08);

    --i-red: #ff2a55;
    --i-red-glow: rgba(255, 42, 85, 0.35);
    --i-red-gradient: linear-gradient(135deg, #ff3366 0%, #e60039 100%);

    --i-cyan: #38bdf8;
    --i-purple: #a855f7;
    --i-emerald: #10b981;

    /* Dark Glass Surfaces */
    --i-bg-glass: rgba(18, 19, 28, 0.72);
    --i-bg-card: rgba(24, 25, 36, 0.85);
    --i-card-inner: rgba(14, 15, 22, 0.65);
    
    /* Precision Borders & Lines */
    --i-border: rgba(255, 255, 255, 0.08);
    --i-border-hover: rgba(255, 255, 255, 0.16);
    --i-border-gold: rgba(245, 184, 0, 0.35);
    --i-line: rgba(255, 255, 255, 0.07);
    --i-line-active: rgba(255, 255, 255, 0.22);

    /* Layout & Base */
    position: relative;
    max-width: 1140px;
    margin: 0 auto;
    padding: 0 24px 60px;
    color: var(--text-primary);
    font-family: 'Outfit', 'Pretendard', -apple-system, BlinkMacSystemFont, sans-serif;
    overflow-x: hidden;
}

/* Dark Theme Background Atmosphere */


/* Subtle Tech Matrix Grid Overlay */
.intro::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image: radial-gradient(rgba(255, 255, 255, 0.07) 1px, transparent 1px);
    background-size: 36px 36px;
    mask-image: radial-gradient(ellipse 85% 65% at 50% 30%, black 15%, transparent 75%);
    -webkit-mask-image: radial-gradient(ellipse 85% 65% at 50% 30%, black 15%, transparent 75%);
    pointer-events: none;
    z-index: 0;
}

.intro > * {
    position: relative;
    z-index: 1;
}

/* Typography Enhancements */
.intro h1,
.intro h2,
.intro h3,
.intro h4,
.intro p {
    word-break: keep-all;
    overflow-wrap: anywhere;
}

/* Metallic & Gradient Stars */
.intro .i-star {
    width: 1em;
    height: 1em;
    vertical-align: -0.12em;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.4));
}
.intro .i-gold { fill: url(#iGold); }
.intro .i-silver { fill: url(#iSilver); }

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.intro .intro-top {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 24px 0;
}
.intro .intro-logo {
    display: inline-flex;
    align-items: center;
    transition: transform .25s ease, opacity .25s ease;
}
.intro .intro-logo:hover {
    transform: translateY(-1px);
    opacity: 0.92;
}
.intro .intro-logo img {
    height: 36px;
    display: block;
    filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.5));
}
.intro .intro-nav {
    display: flex;
    align-items: center;
    gap: 14px;
}
.intro .intro-nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    padding: 6px 12px;
    border-radius: 8px;
    transition: color .2s, background .2s;
}
.intro .intro-nav-link:hover {
    color: #fff;
    background: rgba(255, 255, 255, 0.05);
}
.intro .intro-lang {
    background: rgba(24, 25, 36, 0.9);
    color: var(--text-secondary);
    border: 1px solid var(--i-border);
    border-radius: 10px;
    padding: 7px 12px;
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    backdrop-filter: blur(10px);
    transition: border-color .2s, color .2s;
    outline: none;
}
.intro .intro-lang:hover,
.intro .intro-lang:focus {
    border-color: var(--i-border-hover);
    color: #fff;
}

/* ==========================================================================
   Call-to-Action (CTA) Buttons
   ========================================================================== */
.intro .intro-cta {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
    margin-top: 32px;
}
.intro .intro-btn {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 13px 26px;
    border-radius: 9999px;
    background: var(--i-red-gradient);
    color: #fff;
    font-weight: 600;
    font-size: 15px;
    text-decoration: none;
    box-shadow: 0 8px 25px rgba(255, 42, 85, 0.35), inset 0 1px 0 rgba(255, 255, 255, 0.3);
    transition: transform .25s cubic-bezier(0.4, 0, 0.2, 1), box-shadow .25s ease;
    overflow: hidden;
}
.intro .intro-btn::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.18) 0%, transparent 60%);
    pointer-events: none;
}
.intro .intro-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 14px 34px rgba(255, 42, 85, 0.5), inset 0 1px 0 rgba(255, 255, 255, 0.4);
}
.intro .intro-btn-ghost {
    background: rgba(255, 255, 255, 0.035);
    border: 1px solid rgba(255, 255, 255, 0.12);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2), inset 0 1px 0 rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
    backdrop-filter: blur(12px);
}
.intro .intro-btn-ghost:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.22);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
    color: #fff;
}
.intro .intro-btn-sm {
    padding: 8px 18px;
    font-size: 13px;
    box-shadow: 0 4px 16px rgba(255, 42, 85, 0.3);
}

/* ==========================================================================
   Reveal Animations
   ========================================================================== */
.intro .reveal {
    opacity: 0;
    transform: translateY(26px);
    transition: opacity .8s cubic-bezier(0.16, 1, 0.3, 1), transform .8s cubic-bezier(0.16, 1, 0.3, 1);
}
.intro .reveal.in {
    opacity: 1;
    transform: none;
}

/* ==========================================================================
   Hero Section
   ========================================================================== */
.intro .intro-hero {
    display: grid;
    grid-template-columns: 1.1fr 1fr;
    gap: 48px;
    align-items: center;
    padding: 52px 0 64px;
}
.intro .intro-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 5px 14px;
    border-radius: 999px;
    background: rgba(245, 184, 0, 0.08);
    border: 1px solid rgba(245, 184, 0, 0.25);
    color: var(--i-gold-bright);
    font-size: 13px;
    font-weight: 600;
    letter-spacing: .03em;
    margin: 0 0 18px;
    box-shadow: 0 2px 10px rgba(245, 184, 0, 0.1);
}
.intro .intro-eyebrow .i-star {
    font-size: 14px;
}
.intro .intro-hero h1 {
    font-size: clamp(34px, 4.4vw, 54px);
    line-height: 1.14;
    letter-spacing: -0.02em;
    margin: 0 0 20px;
    font-weight: 700;
    background: linear-gradient(180deg, #ffffff 40%, #c9ccd8 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.intro .intro-lead {
    color: #9ea3b5;
    font-size: 18px;
    line-height: 1.65;
    margin: 0;
}

/* ==========================================================================
   Common Mockup Styling (Video Cards & Skeletons)
   ========================================================================== */
.intro .mini-thumb {
    display: block;
    position: relative;
    border-radius: 8px;
    aspect-ratio: 16 / 9;
    overflow: hidden;
    background: linear-gradient(145deg, #222533 0%, #171822 100%);
    border: 1px solid rgba(255, 255, 255, 0.08);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.1);
}
.intro .mini-thumb::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 75% 25%, rgba(255, 255, 255, 0.1), transparent 65%);
    pointer-events: none;
}
/* Video Timestamp Tag Bar Indicator */
.intro .mini-thumb::after {
    content: '';
    position: absolute;
    right: 5px;
    bottom: 5px;
    width: 20px;
    height: 4px;
    border-radius: 2px;
    background: rgba(255, 255, 255, 0.4);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.6);
}
/* Video Screen Gradations - Modern Cinematic Palettes (Distinct Creator Tones) */
.intro .c1 { background: linear-gradient(140deg, #1e293b 0%, #0f172a 100%); } /* Slate Night */
.intro .c2 { background: linear-gradient(140deg, #2e1065 0%, #170d36 100%); } /* Deep Violet */
.intro .c3 { background: linear-gradient(140deg, #064e3b 0%, #022c22 100%); } /* Dark Emerald */
.intro .c4 { background: linear-gradient(140deg, #312e81 0%, #1e1b4b 100%); } /* Midnight Indigo */
.intro .c5 { background: linear-gradient(140deg, #451a03 0%, #291003 100%); } /* Amber Espresso */
.intro .c6 { background: linear-gradient(140deg, #181926 0%, #0d0e17 100%); } /* Titanium Dark */

.intro .mini-line {
    display: block;
    height: 7px;
    border-radius: 4px;
    background: rgba(255, 255, 255, 0.14);
    margin-top: 8px;
}
.intro .mini-line.short {
    width: 60%;
    background: rgba(255, 255, 255, 0.08);
}

.intro .mini-live {
    position: absolute;
    left: 6px;
    top: 6px;
    font-size: 9px;
    font-weight: 700;
    letter-spacing: .04em;
    background: var(--i-red-gradient);
    color: #fff;
    padding: 2px 6px;
    border-radius: 4px;
    box-shadow: 0 2px 8px rgba(255, 42, 85, 0.6);
    animation: livePulse 2s infinite ease-in-out;
}
@keyframes livePulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: .75; transform: scale(0.96); }
}

/* ==========================================================================
   Hero Visual: Flow (Channels -> Pipeline -> Feed)
   ========================================================================== */
.intro .flow {
    display: grid;
    grid-template-columns: 56px 64px 1fr;
    align-items: center;
    gap: 12px;
    background: linear-gradient(145deg, rgba(23, 25, 37, 0.85) 0%, rgba(15, 16, 24, 0.95) 100%);
    border: 1px solid var(--i-border);
    border-radius: 24px;
    padding: 26px;
    backdrop-filter: blur(20px);
    box-shadow: 0 24px 60px -15px rgba(0, 0, 0, 0.65), inset 0 1px 0 rgba(255, 255, 255, 0.08);
}
.intro .flow-channels {
    display: flex;
    flex-direction: column;
    gap: 11px;
}
.intro .flow-ch {
    width: 46px;
    height: 32px;
    border-radius: 10px;
    display: grid;
    place-items: center;
    background: linear-gradient(145deg, #1d1e29 0%, #101118 100%) !important;
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: #fff;
    font-size: 11px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.1);
    transition: transform .2s, border-color .2s;
}
.intro .flow-ch i {
    filter: drop-shadow(0 1px 2px rgba(0, 0, 0, 0.5));
}
.intro .flow-ch:hover {
    border-color: rgba(255, 42, 85, 0.5);
    transform: scale(1.05);
}

.intro .flow-pipe {
    position: relative;
    height: 220px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.intro .flow-pipe::before {
    content: '';
    position: absolute;
    left: 4px;
    right: 4px;
    top: 50%;
    height: 2px;
    background: linear-gradient(90deg, rgba(255, 255, 255, 0.05) 0%, rgba(245, 184, 0, 0.2) 50%, rgba(255, 255, 255, 0.05) 100%);
    transform: translateY(-50%);
}
.intro .flow-dot {
    position: absolute;
    left: 0;
    top: 50%;
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: #ffe066;
    box-shadow: 0 0 14px var(--i-gold), 0 0 4px #fff;
    opacity: 0;
}
.intro .in .flow-dot {
    animation: travel 2.4s cubic-bezier(0.4, 0, 0.2, 1) infinite;
}
.intro .flow-dot.d2 { animation-delay: .6s !important; top: 32%; }
.intro .flow-dot.d3 { animation-delay: 1.2s !important; top: 68%; }
.intro .flow-dot.d4 { animation-delay: 1.8s !important; top: 48%; }

@keyframes travel {
    0% { left: 0; opacity: 0; transform: scale(0.6); }
    15% { opacity: 1; transform: scale(1); }
    85% { opacity: 1; transform: scale(1); }
    100% { left: calc(100% - 9px); opacity: 0; transform: scale(0.6); }
}

.intro .flow-feed {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
}
.intro .mini-card {
    opacity: 0;
    transform: scale(.88);
    background: rgba(255, 255, 255, 0.02);
    border-radius: 10px;
    padding: 6px;
    border: 1px solid rgba(255, 255, 255, 0.04);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.3);
}
.intro .in .mini-card {
    animation: pop .55s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.intro .in .mini-card.k2 { animation-delay: .22s; }
.intro .in .mini-card.k3 { animation-delay: .44s; }
.intro .in .mini-card.k4 { animation-delay: .66s; }
.intro .in .mini-card.k5 { animation-delay: .88s; }
.intro .in .mini-card.k6 { animation-delay: 1.1s; }

@keyframes pop {
    to { opacity: 1; transform: none; }
}

/* ==========================================================================
   3 Steps Onboarding Bar
   ========================================================================== */
.intro .intro-steps {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    padding: 30px 36px;
    margin-bottom: 48px;
    background: linear-gradient(145deg, rgba(23, 25, 37, 0.7) 0%, rgba(16, 17, 25, 0.8) 100%);
    border: 1px solid var(--i-border);
    border-radius: 22px;
    backdrop-filter: blur(16px);
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.07);
}
.intro .step {
    text-align: center;
    width: 210px;
    position: relative;
    padding: 10px;
}
.intro .step i {
    font-size: 28px;
    color: #e2e4ef;
    filter: drop-shadow(0 2px 6px rgba(0, 0, 0, 0.5));
    transition: transform .25s ease, color .25s ease;
}
/* Step Brand Color Accents */
.intro .step:nth-child(1) i { color: #f1f2f6; }
.intro .step:nth-child(3) i { color: #ff334b; }
.intro .step:nth-child(5) i { color: #ffe066; }

.intro .step:hover i {
    transform: translateY(-2px);
    filter: drop-shadow(0 4px 10px rgba(255, 255, 255, 0.3));
}
.intro .step p {
    margin: 12px 0 0;
    color: #a0a5b8;
    font-size: 14px;
    font-weight: 500;
    line-height: 1.45;
}
.intro .step-n {
    position: absolute;
    top: 0;
    left: calc(50% + 18px);
    width: 22px;
    height: 22px;
    border-radius: 50%;
    background: linear-gradient(135deg, #ffe57f 0%, #f5b800 100%);
    color: #111;
    font-size: 11px;
    font-weight: 800;
    display: grid;
    place-items: center;
    box-shadow: 0 2px 8px rgba(245, 184, 0, 0.5);
}
.intro .step-line {
    flex: 1;
    max-width: 110px;
    height: 2px;
    background: rgba(255, 255, 255, 0.08);
    position: relative;
    overflow: hidden;
    border-radius: 2px;
}
.intro .step-line span {
    position: absolute;
    inset: 0;
    background: linear-gradient(90deg, #f5b800, #ffe57f);
    box-shadow: 0 0 8px var(--i-gold);
    transform: scaleX(0);
    transform-origin: left;
}
.intro .in .step-line span {
    animation: grow 1.2s cubic-bezier(0.16, 1, 0.3, 1) forwards .3s;
}
.intro .in .step-line + .step + .step-line span {
    animation-delay: 1.1s;
}
@keyframes grow {
    to { transform: scaleX(1); }
}

/* ==========================================================================
   Feature Section Common Styling
   ========================================================================== */
.intro .feature {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    padding: 64px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
}
.intro .feature-rev .feature-text {
    order: 2;
}
.intro .feature-tag {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    font-weight: 600;
    color: var(--i-gold-bright);
    background: rgba(245, 184, 0, 0.08);
    border: 1px solid rgba(245, 184, 0, 0.22);
    padding: 6px 14px;
    border-radius: 999px;
    box-shadow: 0 2px 10px rgba(245, 184, 0, 0.06);
}
.intro .feature-tag i {
    font-size: 13px;
    color: var(--i-gold);
}
.intro .feature h2 {
    font-size: clamp(26px, 3.2vw, 36px);
    line-height: 1.22;
    letter-spacing: -0.015em;
    margin: 16px 0 14px;
    background: linear-gradient(180deg, #ffffff 45%, #d1d5e5 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.intro .feature p {
    color: #9ea3b6;
    font-size: 16px;
    line-height: 1.7;
    margin: 0;
}
.intro .feature-visual {
    background: linear-gradient(145deg, rgba(23, 25, 37, 0.75) 0%, rgba(15, 16, 24, 0.88) 100%);
    border: 1px solid var(--i-border);
    border-radius: 24px;
    padding: 30px;
    min-height: 250px;
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(20px);
    box-shadow: 0 24px 50px -12px rgba(0, 0, 0, 0.55), inset 0 1px 0 rgba(255, 255, 255, 0.08);
}
.intro .feature-visual > * {
    width: 100%;
}

/* ==========================================================================
   1. Auto Categories (Sort Demo)
   ========================================================================== */
.intro .sort {
    display: flex;
    flex-direction: column;
    gap: 28px;
}
.intro .sort-pool {
    display: flex;
    justify-content: center;
    gap: 12px;
    min-height: 44px;
}
.intro .sort-bins {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
}
.intro .bin {
    border: 1px solid rgba(255, 255, 255, 0.09);
    background: rgba(255, 255, 255, 0.025);
    border-radius: 14px;
    padding: 16px 8px;
    text-align: center;
    color: #a0a5b8;
    font-size: 13px;
    font-weight: 500;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.25), inset 0 1px 0 rgba(255, 255, 255, 0.04);
    transition: transform .25s, border-color .25s, background .25s;
}
.intro .bin i {
    display: block;
    font-size: 20px;
    margin-bottom: 8px;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.4));
}
/* Category Specific Icon Tone */
.intro .bin:nth-child(1) i { color: #c084fc; } /* Music: Purple/Rose */
.intro .bin:nth-child(2) i { color: #38bdf8; } /* Gaming: Sky/Cyan */
.intro .bin:nth-child(3) i { color: #fbbf24; } /* Education: Gold */

.intro .in .bin {
    animation: binGlow 3.6s ease infinite;
}
.intro .in .bin:nth-child(2) { animation-delay: 1.2s; }
.intro .in .bin:nth-child(3) { animation-delay: 2.4s; }

@keyframes binGlow {
    0%, 30%, 100% {
        border-color: rgba(255, 255, 255, 0.09);
        background: rgba(255, 255, 255, 0.025);
    }
    10%, 20% {
        border-color: rgba(245, 184, 0, 0.5);
        background: rgba(245, 184, 0, 0.08);
        box-shadow: 0 0 20px rgba(245, 184, 0, 0.15), inset 0 1px 0 rgba(255, 255, 255, 0.1);
        color: #fff;
    }
}
.intro .in .sort-pool .flow-ch {
    animation: sortDrop 3.6s cubic-bezier(0.4, 0, 0.2, 1) infinite;
}
.intro .in .sort-pool .s1,
.intro .in .sort-pool .s4 { --dx: -125%; }
.intro .in .sort-pool .s2,
.intro .in .sort-pool .s5 { --dx: 0%; }
.intro .in .sort-pool .s3,
.intro .in .sort-pool .s6 { --dx: 125%; }

.intro .in .sort-pool .s2 { animation-delay: .4s; }
.intro .in .sort-pool .s3 { animation-delay: .8s; }
.intro .in .sort-pool .s4 { animation-delay: 1.2s; }
.intro .in .sort-pool .s5 { animation-delay: 1.6s; }
.intro .in .sort-pool .s6 { animation-delay: 2.0s; }

@keyframes sortDrop {
    0%, 10% { transform: none; opacity: 1; }
    45% { transform: translate(var(--dx), 74px) scale(.6); opacity: 0; }
    46%, 80% { transform: none; opacity: 0; }
    100% { opacity: 1; }
}

/* ==========================================================================
   2. Subscription Feed Stack
   ========================================================================== */
.intro .feed-stack {
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.intro .feed-row {
    display: grid;
    grid-template-columns: 104px 1fr auto;
    gap: 14px;
    align-items: center;
    padding: 10px 12px;
    background: linear-gradient(145deg, rgba(28, 30, 44, 0.8) 0%, rgba(18, 19, 29, 0.9) 100%);
    border: 1px solid rgba(255, 255, 255, 0.07);
    border-radius: 14px;
    opacity: 0;
    transform: translateY(-16px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.35), inset 0 1px 0 rgba(255, 255, 255, 0.05);
}
.intro .in .feed-row {
    animation: drop .55s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.intro .in .feed-row.r2 { animation-delay: .3s; }
.intro .in .feed-row.r3 { animation-delay: .6s; }
.intro .in .feed-row.r4 { animation-delay: .9s; }

@keyframes drop {
    to { opacity: 1; transform: none; }
}
.intro .feed-meta .mini-line:first-child {
    margin-top: 0;
    background: rgba(255, 255, 255, 0.22);
}
.intro .badge-new {
    font-size: 10px;
    font-weight: 700;
    letter-spacing: .04em;
    color: #111;
    background: linear-gradient(135deg, #ffe57f 0%, #f5b800 100%);
    padding: 3px 8px;
    border-radius: 6px;
    box-shadow: 0 2px 8px rgba(245, 184, 0, 0.4);
}

/* ==========================================================================
   3. STAN Demo (Star Transitions: Empty -> Silver -> Gold)
   ========================================================================== */
.intro .stan-demo {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 26px;
}
.intro .stan-big {
    position: relative;
    width: 128px;
    height: 128px;
    display: grid;
    place-items: center;
}
/* Ambient Halo behind the Star */
.intro .stan-big::before {
    content: '';
    position: absolute;
    width: 110px;
    height: 110px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(245, 184, 0, 0.22) 0%, transparent 70%);
    filter: blur(8px);
    pointer-events: none;
}
.intro .stan-big .i-star {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: transform .3s ease;
}
.intro .st-empty,
.intro .st-empty-sm {
    fill: #0c0d14;
    stroke: #484b5c;
    stroke-width: .9;
}
.intro .st-silver {
    fill: url(#iSilver);
    filter: drop-shadow(0 0 12px rgba(220, 230, 245, 0.45));
}
.intro .st-gold {
    fill: url(#iGold);
    filter: drop-shadow(0 0 18px rgba(245, 184, 0, 0.65));
}
.intro .stan-big .st-empty {
    opacity: 1;
}
.intro .in .stan-big .st-empty { animation: s0 6s infinite; }
.intro .in .stan-big .st-silver { animation: s1 6s infinite; }
.intro .in .stan-big .st-gold { animation: s2 6s infinite; }

@keyframes s0 {
    0%, 30% { opacity: 1; }
    33%, 97% { opacity: 0; }
    100% { opacity: 1; }
}
@keyframes s1 {
    0%, 30% { opacity: 0; transform: scale(.8); }
    34% { opacity: 1; transform: scale(1.15); }
    38%, 63% { opacity: 1; transform: none; }
    66%, 100% { opacity: 0; }
}
@keyframes s2 {
    0%, 63% { opacity: 0; transform: scale(.8); }
    67% { opacity: 1; transform: scale(1.18); }
    71%, 96% { opacity: 1; transform: none; }
    100% { opacity: 0; }
}

.intro .stan-tap {
    position: absolute;
    right: -12px;
    bottom: -10px;
    font-size: 26px;
    color: #fff;
    opacity: 0;
    filter: drop-shadow(0 2px 6px rgba(0, 0, 0, 0.6));
}
.intro .in .stan-tap {
    animation: tap 3s infinite;
    animation-delay: 1.4s;
}
@keyframes tap {
    0%, 30% { opacity: 0; transform: translate(12px, 12px); }
    40% { opacity: 1; transform: none; }
    47% { transform: scale(.82); }
    54% { transform: none; }
    70%, 100% { opacity: 0; }
}

.intro .stan-legend {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    justify-content: center;
}
.intro .lg {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 7px 16px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.035);
    border: 1px solid rgba(255, 255, 255, 0.08);
    font-size: 13px;
    font-weight: 500;
    color: #9ea3b5;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.25);
    transition: all .3s ease;
}
.intro .lg .i-star {
    font-size: 16px;
}
.intro .in .lg.l0 { animation: lgOn0 6s infinite; }
.intro .in .lg.l1 { animation: lgOn1 6s infinite 2s; }
.intro .in .lg.l2 { animation: lgOn2 6s infinite 4s; }

@keyframes lgOn0 {
    0%, 32% { border-color: rgba(255, 255, 255, 0.3); color: #fff; background: rgba(255, 255, 255, 0.08); }
    34%, 100% { border-color: rgba(255, 255, 255, 0.08); color: #9ea3b5; background: rgba(255, 255, 255, 0.035); }
}
@keyframes lgOn1 {
    0%, 32% { border-color: rgba(200, 215, 235, 0.5); color: #fff; background: rgba(200, 215, 235, 0.08); box-shadow: 0 0 14px rgba(200, 215, 235, 0.15); }
    34%, 100% { border-color: rgba(255, 255, 255, 0.08); color: #9ea3b5; background: rgba(255, 255, 255, 0.035); }
}
@keyframes lgOn2 {
    0%, 32% { border-color: rgba(245, 184, 0, 0.6); color: #fff; background: rgba(245, 184, 0, 0.1); box-shadow: 0 0 16px rgba(245, 184, 0, 0.2); }
    34%, 100% { border-color: rgba(255, 255, 255, 0.08); color: #9ea3b5; background: rgba(255, 255, 255, 0.035); }
}

/* ==========================================================================
   Intermediate Band (CTA Band)
   ========================================================================== */
.intro .intro-band {
    text-align: center;
    padding: 48px 32px;
    margin: 36px 0;
    border-radius: 24px;
    background: linear-gradient(145deg, rgba(26, 28, 42, 0.8) 0%, rgba(16, 17, 26, 0.9) 100%);
    border: 1px solid var(--i-border);
    backdrop-filter: blur(20px);
    box-shadow: 0 20px 48px rgba(0, 0, 0, 0.45), inset 0 1px 0 rgba(255, 255, 255, 0.08);
}
.intro .intro-band h3 {
    font-size: clamp(22px, 2.8vw, 30px);
    letter-spacing: -0.015em;
    margin: 0;
    background: linear-gradient(180deg, #ffffff 40%, #c9ccd8 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.intro .intro-band .intro-cta {
    justify-content: center;
    margin-top: 24px;
}

/* ==========================================================================
   4. LOOP Demo
   ========================================================================== */
.intro .loop-demo {
    display: flex;
    flex-direction: column;
    gap: 18px;
}
.intro .loop-cards {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
}
.intro .loop-card {
    position: relative;
    border-radius: 12px;
    padding: 5px;
    border: 2px solid transparent;
    background: rgba(255, 255, 255, 0.02);
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.3);
    transition: transform .25s ease, border-color .25s ease;
}
.intro .loop-card.off {
    opacity: .35;
}
.intro .i-loop-check {
    position: absolute;
    top: 9px;
    right: 9px;
    width: 20px;
    height: 20px;
    border-radius: 6px;
    background: linear-gradient(135deg, #ffe57f 0%, #f5b800 100%);
    color: #111;
    display: grid;
    place-items: center;
    font-size: 11px;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.4);
}
.intro .loop-card.off .i-loop-check {
    background: rgba(15, 16, 22, 0.8);
    border: 1px solid rgba(255, 255, 255, 0.3);
    color: transparent;
    box-shadow: none;
}
.intro .loop-play {
    position: absolute;
    inset: 5px;
    display: grid;
    place-items: center;
    font-size: 22px;
    color: #fff;
    opacity: 0;
    border-radius: 8px;
    background: rgba(0, 0, 0, 0.45);
    backdrop-filter: blur(2px);
    filter: drop-shadow(0 2px 8px rgba(0, 0, 0, 0.6));
}

.intro .in .lc1 { animation: loopOn 4.5s infinite; }
.intro .in .lc2 { animation: loopOn 4.5s infinite 1.5s; }
.intro .in .lc4 { animation: loopOn 4.5s infinite 3s; }

.intro .in .lc1 .loop-play { animation: loopPlay 4.5s infinite; }
.intro .in .lc2 .loop-play { animation: loopPlay 4.5s infinite 1.5s; }
.intro .in .lc4 .loop-play { animation: loopPlay 4.5s infinite 3s; }

@keyframes loopOn {
    0%, 30% {
        border-color: var(--i-gold);
        transform: translateY(-5px);
        box-shadow: 0 8px 24px rgba(245, 184, 0, 0.25);
    }
    34%, 100% {
        border-color: transparent;
        transform: none;
        box-shadow: 0 4px 14px rgba(0, 0, 0, 0.3);
    }
}
@keyframes loopPlay {
    0%, 30% { opacity: 1; }
    34%, 100% { opacity: 0; }
}

.intro .loop-bar {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 18px;
    border-radius: 14px;
    background: linear-gradient(145deg, rgba(28, 30, 44, 0.85) 0%, rgba(18, 19, 29, 0.95) 100%);
    border: 1px solid rgba(255, 255, 255, 0.08);
    font-weight: 600;
    letter-spacing: .03em;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.35);
}
.intro .loop-bar .fa-repeat {
    color: var(--i-gold-bright);
    font-size: 15px;
}
.intro .fa-spin-slow {
    animation: fa-spin 3.5s linear infinite;
}
.intro .loop-count {
    color: #9ea3b6;
    font-weight: 500;
    font-size: 13px;
    background: rgba(255, 255, 255, 0.05);
    padding: 3px 10px;
    border-radius: 6px;
}
.intro .loop-off {
    margin-left: auto;
    font-size: 12px;
    color: #8b90a4;
    border: 1px solid rgba(255, 255, 255, 0.1);
    background: rgba(255, 255, 255, 0.02);
    padding: 4px 10px;
    border-radius: 8px;
}

/* ==========================================================================
   5. Channel Search Demo
   ========================================================================== */
.intro .search-demo {
    display: flex;
    flex-direction: column;
    gap: 14px;
}
.intro .search-box {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 20px;
    border-radius: 999px;
    background: linear-gradient(145deg, rgba(28, 30, 44, 0.9) 0%, rgba(18, 19, 29, 0.95) 100%);
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: #9ea3b6;
    font-size: 14px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35), inset 0 1px 0 rgba(255, 255, 255, 0.05);
}
.intro .search-box i {
    color: var(--i-gold);
}
.intro .typing {
    display: inline-block;
    overflow: hidden;
    white-space: nowrap;
    width: 0;
    border-right: 2px solid var(--i-gold);
    color: #fff;
    font-weight: 500;
}
.intro .in .typing {
    animation: type 1.6s steps(15) forwards .3s, caret .8s step-end infinite;
}
@keyframes type {
    to { width: 15ch; }
}
@keyframes caret {
    50% { border-color: transparent; }
}
.intro .search-results {
    display: flex;
    flex-direction: column;
    gap: 10px;
}
.intro .sr {
    display: grid;
    grid-template-columns: 96px 1fr;
    gap: 14px;
    align-items: center;
    padding: 10px 12px;
    background: linear-gradient(145deg, rgba(28, 30, 44, 0.75) 0%, rgba(18, 19, 29, 0.85) 100%);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 12px;
    opacity: 0;
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.3);
}
.intro .in .sr {
    animation: pop .45s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.intro .in .sr1 { animation-delay: 2s; }
.intro .in .sr2 { animation-delay: 2.25s; }
.intro .in .sr3 { animation-delay: 2.5s; }

/* ==========================================================================
   6. View Trend Chart Demo
   ========================================================================== */
.intro .chart-demo {
    display: flex;
    flex-direction: column;
    align-items: center;
}
.intro .chart {
    width: 100%;
    height: auto;
    overflow: visible;
}
.intro .chart .grid line {
    stroke: rgba(255, 255, 255, 0.07);
    stroke-dasharray: 4 6;
}
.intro .chart path {
    fill: none;
    stroke-width: 3.5;
    stroke-linecap: round;
    stroke-dasharray: 450;
    stroke-dashoffset: 450;
}
.intro .line-views {
    stroke: url(#iViews);
    filter: drop-shadow(0 0 8px rgba(56, 189, 248, 0.5));
}
.intro .line-likes {
    stroke: url(#iLikes);
    filter: drop-shadow(0 0 8px rgba(245, 184, 0, 0.55));
}
.intro .in .chart path {
    animation: draw 2.2s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.intro .in .chart .line-likes {
    animation-delay: .4s;
}
@keyframes draw {
    to { stroke-dashoffset: 0; }
}

.intro .dot-end {
    fill: #38bdf8;
    stroke: #0c0d14;
    stroke-width: 2;
    opacity: 0;
    filter: drop-shadow(0 0 10px #38bdf8);
}
.intro .in .dot-end {
    animation: pop .3s forwards 2.2s, pulse 1.8s infinite 2.5s;
}
.intro .chart-legend {
    display: flex;
    gap: 20px;
    margin-top: 16px;
    font-size: 13px;
    font-weight: 500;
    color: #a0a5b8;
}
.intro .chart-legend i {
    display: inline-block;
    width: 16px;
    height: 4px;
    border-radius: 2px;
    vertical-align: middle;
    margin-right: 6px;
}
.intro .k-views i {
    background: linear-gradient(90deg, #818cf8, #38bdf8);
    box-shadow: 0 0 6px rgba(56, 189, 248, 0.6);
}
.intro .k-likes i {
    background: linear-gradient(90deg, #ffd84a, #f59e0b);
    box-shadow: 0 0 6px rgba(245, 184, 0, 0.6);
}

/* ==========================================================================
   7. Watch Counter Demo
   ========================================================================== */
.intro .watch-demo {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}
.intro .watch-num {
    background: linear-gradient(145deg, rgba(28, 30, 44, 0.8) 0%, rgba(18, 19, 29, 0.9) 100%);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 18px;
    padding: 24px 16px;
    text-align: center;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35), inset 0 1px 0 rgba(255, 255, 255, 0.06);
}
.intro .watch-num .count {
    display: block;
    font-size: 48px;
    font-weight: 800;
    letter-spacing: -0.02em;
    background: linear-gradient(180deg, #ffe57f 0%, #f5b800 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    filter: drop-shadow(0 4px 12px rgba(245, 184, 0, 0.25));
}
.intro .watch-num small {
    display: block;
    color: #9ea3b6;
    font-size: 13px;
    font-weight: 500;
    margin-top: 4px;
}
.intro .watch-progress {
    grid-column: 1 / -1;
    height: 8px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.07);
    overflow: hidden;
    box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.4);
}
.intro .watch-progress span {
    display: block;
    height: 100%;
    width: 0;
    background: linear-gradient(90deg, #f5b800 0%, #ffe066 100%);
    box-shadow: 0 0 12px rgba(245, 184, 0, 0.6);
    border-radius: 999px;
}
.intro .in .watch-progress span {
    animation: fill 2.4s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
@keyframes fill {
    to { width: 95%; }
}

/* ==========================================================================
   Live Schedule Demo
   ========================================================================== */
.intro .sd-demo {
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.intro .sd-row {
    display: grid;
    grid-template-columns: 76px 1fr 38px;
    align-items: center;
    gap: 14px;
    padding: 10px 12px;
    border-radius: 14px;
    background: linear-gradient(145deg, rgba(28, 30, 44, 0.85) 0%, rgba(18, 19, 29, 0.95) 100%);
    border: 1px solid rgba(255, 255, 255, 0.09);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
    opacity: 0;
    transform: translateX(-24px);
}
.intro .in .sd-row {
    animation: slideIn .5s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.intro .in .sd2 { animation-delay: .3s; }
.intro .in .sd3 { animation-delay: .6s; }
@keyframes slideIn {
    to { opacity: 1; transform: none; }
}
.intro .sd-thumb {
    display: block;
    height: 44px;
    border-radius: 8px;
}
.intro .sd-thumb.c1 { background: linear-gradient(135deg, #ff3366 0%, #7c1d4f 100%); }
.intro .sd-thumb.c2 { background: linear-gradient(135deg, #38bdf8 0%, #1e3a8a 100%); }
.intro .sd-thumb.c3 { background: linear-gradient(135deg, #a855f7 0%, #4c1d95 100%); }
.intro .sd-when {
    min-width: 0;
    color: #e6e8f0;
    font-size: 14px;
    font-weight: 600;
    overflow-wrap: anywhere;
}
.intro .sd-live { color: var(--i-red); }
.intro .sd-dot {
    justify-self: center;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--i-red);
    box-shadow: 0 0 10px var(--i-red-glow);
    animation: livePulse 1.6s ease-in-out infinite;
}
.intro .sd-cal {
    position: relative;
    display: grid;
    place-items: center;
    width: 38px;
    height: 38px;
    border-radius: 10px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    color: #c6cada;
    font-size: 16px;
}
.intro .sd-cal i { grid-area: 1 / 1; }
.intro .sd-added .fa-check {
    opacity: 0;
    color: #10b981;
}
.intro .in .sd-added {
    animation: sdAddBox .4s ease 1.5s forwards;
}
.intro .in .sd-added .fa-calendar-plus {
    animation: sdHide .3s ease 1.5s forwards;
}
.intro .in .sd-added .fa-check {
    animation: sdShow .3s ease 1.5s forwards;
}
@keyframes sdAddBox {
    to { border-color: rgba(16, 185, 129, 0.6); background: rgba(16, 185, 129, 0.12); }
}
@keyframes sdHide {
    to { opacity: 0; }
}
@keyframes sdShow {
    to { opacity: 1; }
}

/* ==========================================================================
   Google Data & Trust Section (OAuth Verification Standards)
   ========================================================================== */
.intro .intro-data {
    padding: 64px 0 32px;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
}
.intro .intro-data h2 {
    font-size: clamp(24px, 3vw, 32px);
    letter-spacing: -0.015em;
    margin: 0 0 28px;
    background: linear-gradient(180deg, #ffffff 40%, #c9ccd8 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.intro .intro-data h2 i {
    color: var(--i-gold);
    -webkit-text-fill-color: initial;
    margin-right: 8px;
    font-size: 26px;
    vertical-align: -0.08em;
}
.intro .data-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);  /* 카드 4개(AI 분류 추가, 11-03) → 2×2 */
    gap: 20px;
}
.intro .data-item {
    background: linear-gradient(145deg, rgba(23, 25, 37, 0.7) 0%, rgba(16, 17, 26, 0.8) 100%);
    border: 1px solid var(--i-border);
    border-radius: 20px;
    padding: 26px 22px;
    backdrop-filter: blur(16px);
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.35), inset 0 1px 0 rgba(255, 255, 255, 0.06);
    transition: transform .25s ease, border-color .25s ease;
}
.intro .data-item:hover {
    transform: translateY(-2px);
    border-color: rgba(255, 255, 255, 0.15);
}
.intro .data-item > i {
    font-size: 22px;
    width: 44px;
    height: 44px;
    display: grid;
    place-items: center;
    border-radius: 12px;
    margin-bottom: 16px;
}
/* Individual Data Security Item Colors */
.intro .data-item:nth-child(1) > i {
    color: #ff334b;
    background: rgba(255, 51, 75, 0.09);
    border: 1px solid rgba(255, 51, 75, 0.22);
}
.intro .data-item:nth-child(2) > i {
    color: #38bdf8;
    background: rgba(56, 189, 248, 0.09);
    border: 1px solid rgba(56, 189, 248, 0.22);
}
.intro .data-item:nth-child(3) > i {
    color: #f5b800;
    background: rgba(245, 184, 0, 0.09);
    border: 1px solid rgba(245, 184, 0, 0.22);
}

.intro .data-item h4 {
    margin: 0 0 10px;
    font-size: 17px;
    font-weight: 600;
    color: #fff;
    letter-spacing: -0.01em;
}
.intro .data-item p {
    margin: 0;
    color: #9ea3b5;
    font-size: 14px;
    line-height: 1.65;
}
.intro .data-note {
    color: #797e93;
    font-size: 13px;
    line-height: 1.65;
    margin: 28px 0 12px;
}
.intro .data-links {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    font-size: 13px;
}
.intro .data-links a,
.intro .intro-foot a {
    color: #a0a5b8;
    text-decoration: none;
    transition: color .2s ease;
}
.intro .data-links a:hover,
.intro .intro-foot a:hover {
    color: #fff;
    text-decoration: underline;
}
.intro .data-links span {
    color: #55596b;
}

/* ==========================================================================
   Footer
   ========================================================================== */
.intro .intro-band-last {
    margin-top: 48px;
}
.intro .intro-foot {
    text-align: center;
    color: #74798e;
    font-size: 13px;
    padding: 36px 0 16px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}
.intro .intro-foot p {
    margin: 8px 0;
}
.intro .intro-foot-op {
    font-size: 12px;
    color: #5d6174;
}

/* ==========================================================================
   Responsive Adaptations
   ========================================================================== */
@media (max-width: 880px) {
    .intro {
        padding: 0 18px 40px;
    }
    .intro .intro-hero,
.intro .feature {
        grid-template-columns: 1fr;
        gap: 36px;
    }
    .intro .feature-rev .feature-text {
        order: 0;
    }
    .intro .intro-hero {
        padding: 28px 0 44px;
    }
    .intro .intro-steps {
        flex-direction: column;
        gap: 20px;
        padding: 24px;
    }
    .intro .step-line {
        width: 2px;
        height: 28px;
        max-width: none;
        flex: none;
    }
    .intro .step-line span {
        transform: scaleY(0);
        transform-origin: top;
    }
    @keyframes grow {
        to { transform: scale(1); }
    }
    .intro .data-grid {
        grid-template-columns: 1fr;
        gap: 14px;
    }
    .intro .intro-nav-link {
        display: none;
    }
}

@media (max-width: 480px) {
    .intro .flow {
        grid-template-columns: 44px 36px 1fr;
        padding: 16px;
        border-radius: 18px;
    }
    .intro .flow-ch {
        width: 38px;
        height: 26px;
        border-radius: 8px;
        font-size: 10px;
    }
    .intro .feature-visual {
        padding: 18px;
        border-radius: 18px;
    }
    .intro .intro-btn {
        flex: 1;
        justify-content: center;
    }
    .intro .intro-top .intro-btn {
        flex: none;
    }
    .intro .loop-cards {
        gap: 6px;
    }
    .intro .watch-num .count {
        font-size: 38px;
    }
}

/* ==========================================================================
   Accessibility: Reduced Motion
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
    .intro *,
.intro *::before,
.intro *::after {
        animation: none !important;
        transition: none !important;
    }
    .intro .reveal,
.intro .mini-card,
.intro .feed-row,
.intro .sr,
.intro .sd-row {
        opacity: 1 !important;
        transform: none !important;
    }
    .intro .typing {
        width: auto;
    }
    .intro .chart path {
        stroke-dashoffset: 0;
    }
    .intro .stan-big .st-gold {
        opacity: 1;
    }
}