@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@300;400;500;700;900&display=swap');

:root {
    --primary: #4F46E5;
    --primary-light: #818CF8;
    --primary-dark: #3730A3;
    --accent: #F59E0B;
    --accent-glow: rgba(245, 158, 11, 0.25);
    --bg-body: #F0F2F8;
    --bg-white: #FFFFFF;
    --bg-hero: linear-gradient(135deg, #1E1B4B 0%, #312E81 40%, #4338CA 100%);
    --text-dark: #1E1B4B;
    --text-body: #4B5563;
    --text-muted: #9CA3AF;
    --border: rgba(79, 70, 229, 0.12);
    --shadow-sm: 0 2px 8px rgba(30, 27, 75, 0.06);
    --shadow-md: 0 8px 30px rgba(30, 27, 75, 0.1);
    --shadow-lg: 0 20px 60px rgba(30, 27, 75, 0.15);
    --radius: 16px;
    --radius-sm: 10px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-body);
    color: var(--text-body);
    line-height: 1.8;
    -webkit-font-smoothing: antialiased;
}

/* ===== Container ===== */
.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* ===== Hero Banner ===== */
.hero {
    background: var(--bg-hero);
    padding: 5rem 0 4rem;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -30%;
    width: 160%;
    height: 200%;
    background: radial-gradient(ellipse at center, rgba(129, 140, 248, 0.15) 0%, transparent 60%);
    animation: heroGlow 8s ease-in-out infinite alternate;
}

@keyframes heroGlow {
    0% {
        transform: translate(0, 0) scale(1);
    }

    100% {
        transform: translate(5%, -5%) scale(1.1);
    }
}

.hero-tag {
    display: inline-block;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.15);
    color: rgba(255, 255, 255, 0.9);
    padding: 0.4rem 1.2rem;
    border-radius: 50px;
    font-size: 0.85rem;
    margin-bottom: 1.5rem;
    letter-spacing: 2px;
    position: relative;
    z-index: 1;
}

.hero h1 {
    color: #FFFFFF;
    font-size: 2.8rem;
    font-weight: 900;
    line-height: 1.3;
    margin-bottom: 1rem;
    position: relative;
    z-index: 1;
}

.hero h1 .highlight {
    background: linear-gradient(90deg, var(--accent), #FBBF24);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-sub {
    color: rgba(255, 255, 255, 0.7);
    font-size: 1.1rem;
    max-width: 700px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

/* ===== Section Layout ===== */
.section {
    padding: 3rem 0;
}

.section-card {
    background: var(--bg-white);
    border-radius: var(--radius);
    padding: 2.5rem;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border);
    margin-bottom: 1.5rem;
    transition: var(--transition);
}

.section-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 1.2rem;
    display: flex;
    align-items: center;
    gap: 0.6rem;
}

.section-title::before {
    content: '';
    display: inline-block;
    width: 4px;
    height: 1.5rem;
    background: linear-gradient(180deg, var(--primary), var(--primary-light));
    border-radius: 2px;
}

.section-body {
    font-size: 0.95rem;
    line-height: 2;
}

.section-body p {
    margin-bottom: 0.8rem;
    text-indent: 2em;
}

/* ===== Overview Cards ===== */
.overview-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin-top: 1rem;
}

.overview-item {
    background: linear-gradient(135deg, #EEF2FF, #E0E7FF);
    border-radius: var(--radius-sm);
    padding: 1.2rem 1.5rem;
    text-align: center;
}

.overview-item .label {
    font-size: 0.8rem;
    color: var(--primary);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 0.3rem;
}

.overview-item .value {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-dark);
}

/* ===== VIP Tiers ===== */
.vip-tiers {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin: 1rem 0;
}

.vip-tier {
    border-radius: var(--radius-sm);
    padding: 1.5rem;
    position: relative;
    overflow: hidden;
    transition: var(--transition);
    text-align: left;
}

.vip-tier:hover {
    transform: scale(1.02);
}

.vip-tier.tier-1 {
    background: linear-gradient(135deg, #FFFBEB, #FEF3C7);
    border: 1px solid rgba(245, 158, 11, 0.2);
}

.vip-tier.tier-2 {
    background: linear-gradient(135deg, #EFF6FF, #DBEAFE);
    border: 1px solid rgba(59, 130, 246, 0.2);
}

.vip-tier.tier-3 {
    background: linear-gradient(135deg, #F5F3FF, #EDE9FE);
    border: 1px solid rgba(139, 92, 246, 0.3);
}

.vip-tier .tier-head {
    display: flex;
    align-items: center;
    gap: 0.8rem;
    margin-bottom: 0.6rem;
}

.vip-tier .tier-icon {
    font-size: 1.6rem;
}

.vip-tier .tier-label {
    font-weight: 700;
    color: var(--text-dark);
    font-size: 1.05rem;
}

.vip-tier .tier-desc {
    font-size: 0.9rem;
    color: var(--text-body);
}

/* ===== Service List ===== */
.service-list {
    list-style: none;
    margin-top: 1rem;
}

.service-list li {
    padding: 0.8rem 0;
    border-bottom: 1px solid rgba(79, 70, 229, 0.06);
    display: flex;
    align-items: flex-start;
    gap: 0.8rem;
    font-size: 0.95rem;
}

.service-list li:last-child {
    border-bottom: none;
}

.service-list .icon {
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    margin-top: 2px;
}

/* ===== Value Grid ===== */
.value-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin-top: 1rem;
}

.value-card {
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.04), rgba(129, 140, 248, 0.08));
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 1.5rem;
    text-align: left;
    transition: var(--transition);
}

.value-card:hover {
    border-color: var(--primary-light);
    box-shadow: var(--shadow-sm);
}

.value-card .v-head {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    margin-bottom: 0.8rem;
}

.value-card .v-icon {
    font-size: 1.8rem;
}

.value-card .v-title {
    font-weight: 700;
    color: var(--text-dark);
    font-size: 1rem;
}

.value-card .v-desc {
    font-size: 0.85rem;
    color: var(--text-body);
}

/* ===== Feature Tabs (Teacher / Student) ===== */
.feature-block {
    margin-top: 1.5rem;
}

.feature-role {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--primary-dark);
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--primary-light);
    display: inline-block;
}

.feature-items {
    display: grid;
    gap: 0.8rem;
    margin-bottom: 2rem;
}

.feature-item {
    display: flex;
    gap: 1rem;
    align-items: flex-start;
    padding: 1rem 1.2rem;
    background: rgba(79, 70, 229, 0.03);
    border-radius: var(--radius-sm);
    border: 1px solid transparent;
    transition: var(--transition);
}

.feature-item:hover {
    background: rgba(79, 70, 229, 0.06);
    border-color: var(--border);
}

.feature-item .f-icon {
    font-size: 1.3rem;
    flex-shrink: 0;
    margin-top: 2px;
}

.feature-item .f-title {
    font-weight: 600;
    color: var(--text-dark);
    font-size: 0.95rem;
}

.feature-item .f-desc {
    font-size: 0.88rem;
    color: var(--text-body);
    margin-top: 2px;
}

/* ===== How to Join ===== */
.join-methods {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
    margin-top: 1rem;
}

.join-method {
    background: linear-gradient(135deg, #EEF2FF, #E0E7FF);
    border-radius: var(--radius-sm);
    padding: 1.5rem;
    text-align: center;
    transition: var(--transition);
}

.join-method:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-sm);
}

.join-method .j-icon {
    font-size: 2.5rem;
    margin-bottom: 0.8rem;
}

.join-method .j-title {
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 0.4rem;
}

.join-method .j-desc {
    font-size: 0.88rem;
    color: var(--text-body);
    line-height: 1.6;
}

.join-method a {
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
    border-bottom: 1px dashed var(--primary-light);
}

.join-method a:hover {
    color: var(--primary-dark);
}

/* ===== CTA Banner ===== */
.cta-banner {
    background: var(--bg-hero);
    border-radius: var(--radius);
    padding: 3rem 2rem;
    text-align: center;
    margin: 1rem 0 3rem;
    position: relative;
    overflow: hidden;
}

.cta-banner::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 30% 50%, rgba(245, 158, 11, 0.15) 0%, transparent 50%);
}

.cta-banner p {
    color: rgba(255, 255, 255, 0.95);
    font-size: 1.3rem;
    font-weight: 700;
    position: relative;
    z-index: 1;
}

.cta-banner .cta-sub {
    font-size: 1rem;
    font-weight: 400;
    color: rgba(255, 255, 255, 0.6);
    margin-top: 0.5rem;
}

/* ===== Floating QR Code ===== */
.qr-float {
    position: fixed;
    right: 2rem;
    top: 50%;
    transform: translateY(-50%);
    z-index: 999;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.6rem;
    animation: qrSlideIn 0.8s ease-out;
}

@keyframes qrSlideIn {
    from {
        opacity: 0;
        transform: translateY(-50%) translateX(60px);
    }

    to {
        opacity: 1;
        transform: translateY(-50%) translateX(0);
    }
}

.qr-float .qr-card {
    background: var(--bg-white);
    border-radius: var(--radius);
    padding: 1rem;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border);
    text-align: center;
    transition: var(--transition);
}

.qr-float .qr-card:hover {
    box-shadow: 0 24px 64px rgba(30, 27, 75, 0.22);
    transform: scale(1.05);
}

.qr-float .qr-card img {
    width: 120px;
    height: 120px;
    display: block;
    border-radius: var(--radius-sm);
}

.qr-float .qr-label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-body);
    letter-spacing: 1px;
}

@keyframes labelPulse {

    0%,
    100% {
        box-shadow: 0 4px 15px rgba(79, 70, 229, 0.4);
    }

    50% {
        box-shadow: 0 4px 25px rgba(79, 70, 229, 0.6);
    }
}

/* ===== Footer ===== */
.footer {
    background: var(--text-dark);
    color: rgba(255, 255, 255, 0.5);
    text-align: center;
    padding: 2.5rem 0;
    font-size: 0.85rem;
}

.footer a {
    color: rgba(255, 255, 255, 0.5);
    text-decoration: none;
    transition: var(--transition);
}

.footer a:hover {
    color: rgba(255, 255, 255, 0.8);
}

/* ===== Mobile Fixed Bottom CTA ===== */
.mobile-cta-bar {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--bg-white);
    padding: 0.8rem 1rem;
    box-shadow: 0 -4px 20px rgba(30, 27, 75, 0.12);
    border-top: 1px solid var(--border);
}

.mobile-cta-bar a {
    display: block;
    width: 100%;
    padding: 0.9rem;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: white;
    text-align: center;
    border-radius: 50px;
    font-size: 1.05rem;
    font-weight: 700;
    text-decoration: none;
    box-shadow: 0 6px 20px rgba(79, 70, 229, 0.4);
    transition: var(--transition);
    letter-spacing: 2px;
}

.mobile-cta-bar a:active {
    transform: scale(0.97);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .hero {
        padding: 3.5rem 0 2.5rem;
    }

    .hero h1 {
        font-size: 1.8rem;
    }

    .hero-sub {
        font-size: 0.95rem;
    }

    .section-card {
        padding: 1.5rem;
        border-radius: var(--radius-sm);
    }

    .section-title {
        font-size: 1.25rem;
    }

    .overview-grid {
        grid-template-columns: 1fr;
        gap: 0.6rem;
    }

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

    .overview-item {
        display: flex;
        justify-content: space-between;
        align-items: center;
        text-align: left;
    }

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

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

    /* Hide desktop QR, show mobile CTA bar */
    .qr-float {
        display: none !important;
    }

    .mobile-cta-bar {
        display: block !important;
    }

    .container {
        padding: 0 1rem;
    }

    .cta-banner {
        padding: 2rem 1.5rem;
    }

    .cta-banner p {
        font-size: 1.1rem;
    }

    /* Add bottom padding so content isn't hidden behind fixed CTA */
    .footer {
        padding-bottom: 5rem;
    }
}

@media (min-width: 769px) {
    .mobile-cta-bar {
        display: none !important;
    }
}

/* ===== Activity Ended Modal ===== */
.ended-overlay {
    position: fixed;
    inset: 0;
    background: rgba(30, 27, 75, 0.4);
    backdrop-filter: blur(8px);
    z-index: 10000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.ended-modal {
    background: var(--bg-white);
    max-width: 400px;
    width: 100%;
    border-radius: var(--radius);
    padding: 2.5rem;
    text-align: center;
    box-shadow: 0 40px 100px rgba(30, 27, 75, 0.25);
    border: 1px solid rgba(255, 255, 255, 0.6);
    animation: modalPopIn 0.5s cubic-bezier(0.19, 1, 0.22, 1);
}

@keyframes modalPopIn {
    from {
        opacity: 0;
        transform: scale(0.9) translateY(20px);
    }
    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

.ended-icon {
    font-size: 3.5rem;
    margin-bottom: 1rem;
}

.ended-modal h2 {
    color: var(--text-dark);
    font-size: 1.6rem;
    font-weight: 800;
    margin-bottom: 0.8rem;
}

.ended-modal p {
    font-size: 0.95rem;
    color: var(--text-body);
    line-height: 1.6;
    margin-bottom: 2rem;
}

.btn-confirm {
    background: var(--primary);
    color: white;
    border: none;
    padding: 0.8rem 2.5rem;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 4px 15px rgba(79, 70, 229, 0.3);
}

.btn-confirm:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(79, 70, 229, 0.4);
}

/* Grayed out QR for end status */
.qr-ended .qr-card img {
    filter: grayscale(1) !important;
    opacity: 0.5 !important;
}
.qr-ended .qr-label {
    color: var(--text-muted) !important;
}