/* ==========================================================================
   JADOO THEME — MINIMALIST & ELEGANT STYLESHEET
   Phan Hoàng Vũ — MSSV: 20235462
   ========================================================================== */

:root {
    /* Color Palette — Jadoo Inspired */
    --bg-page: #FFFDF9;
    --bg-card: #FFFFFF;
    --bg-card-alt: #FDF7F2;
    --bg-subtle: #F8F4F0;

    --text-heading: #181E4B;
    --text-body: #5E6282;
    --text-muted: #84889A;

    --accent-orange: #F1A501;
    --accent-coral: #DF6951;
    --accent-purple: #7B61FF;
    --accent-green: #00B074;
    --accent-blue: #2288FF;

    --border-color: rgba(24, 30, 75, 0.08);
    --shadow-card: 0px 20px 50px rgba(223, 105, 81, 0.08), 0px 10px 25px rgba(0, 0, 0, 0.04);
    --shadow-hover: 0px 25px 60px rgba(223, 105, 81, 0.16), 0px 12px 30px rgba(0, 0, 0, 0.08);
    --shadow-btn: 0px 15px 30px rgba(241, 165, 1, 0.28);
    --shadow-coral: 0px 15px 30px rgba(223, 105, 81, 0.28);

    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 24px;
    --radius-full: 9999px;

    --font-heading: 'Volkhov', Georgia, serif;
    --font-sans: 'Poppins', 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
    --transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Dark Theme Variables */
body.dark-theme {
    --bg-page: #101426;
    --bg-card: #181E38;
    --bg-card-alt: #1F2749;
    --bg-subtle: #151A33;

    --text-heading: #F8FAFC;
    --text-body: #A0AEC0;
    --text-muted: #718096;

    --border-color: rgba(255, 255, 255, 0.1);
    --shadow-card: 0px 20px 45px rgba(0, 0, 0, 0.4);
    --shadow-hover: 0px 25px 60px rgba(0, 0, 0, 0.6);
    --shadow-btn: 0px 15px 30px rgba(241, 165, 1, 0.2);
    --shadow-coral: 0px 15px 30px rgba(223, 105, 81, 0.2);
}

/* Global Reset */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-page);
    color: var(--text-body);
    line-height: 1.65;
    position: relative;
    overflow-x: hidden;
    transition: background-color 0.4s ease, color 0.4s ease;
}

/* Ambient Background Blobs (Jadoo Style) */
.blob-top-right {
    position: fixed;
    top: -80px;
    right: -80px;
    width: 580px;
    height: 580px;
    background: radial-gradient(circle, rgba(255, 241, 218, 0.85) 0%, rgba(254, 230, 190, 0.4) 50%, transparent 75%);
    border-radius: 50%;
    z-index: -1;
    pointer-events: none;
    filter: blur(40px);
}

.blob-center-left {
    position: fixed;
    top: 45%;
    left: -120px;
    width: 450px;
    height: 450px;
    background: radial-gradient(circle, rgba(255, 225, 218, 0.6) 0%, rgba(255, 238, 230, 0.2) 60%, transparent 75%);
    border-radius: 50%;
    z-index: -1;
    pointer-events: none;
    filter: blur(50px);
}

body.dark-theme .blob-top-right {
    background: radial-gradient(circle, rgba(241, 165, 1, 0.15) 0%, transparent 70%);
}

body.dark-theme .blob-center-left {
    background: radial-gradient(circle, rgba(223, 105, 81, 0.12) 0%, transparent 70%);
}

/* Links & General */
a {
    color: inherit;
    text-decoration: none;
}

/* ==========================================================================
   NAVIGATION BAR
   ========================================================================== */
.navbar {
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    background: rgba(255, 253, 249, 0.85);
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition);
}

body.dark-theme .navbar {
    background: rgba(16, 20, 38, 0.85);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 18px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: inline-flex;
    align-items: center;
}

.logo-main {
    font-family: var(--font-sans);
    font-size: 1.8rem;
    font-weight: 800;
    color: var(--text-heading);
    letter-spacing: -0.5px;
}

.logo-dot {
    color: var(--accent-coral);
    font-size: 2.2rem;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-link {
    font-size: 1rem;
    font-weight: 500;
    color: var(--text-heading);
    transition: var(--transition);
    position: relative;
    padding: 6px 0;
}

.nav-link:hover,
.nav-link.active {
    color: var(--accent-coral);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: var(--accent-coral);
    border-radius: 2px;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

.btn-icon {
    background: none;
    border: 1px solid var(--border-color);
    width: 42px;
    height: 42px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--text-heading);
    transition: var(--transition);
}

.btn-icon:hover {
    border-color: var(--accent-orange);
    color: var(--accent-orange);
    transform: rotate(15deg);
}

.btn-icon svg {
    width: 20px;
    height: 20px;
}

body.light-theme .moon-icon { display: block; }
body.light-theme .sun-icon { display: none; }
body.dark-theme .moon-icon { display: none; }
body.dark-theme .sun-icon { display: block; }

.btn-primary {
    background: transparent;
    border: 1px solid var(--text-heading);
    color: var(--text-heading);
    padding: 10px 22px;
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-weight: 500;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
}

.btn-primary:hover {
    background: var(--text-heading);
    color: #FFFFFF;
}

body.dark-theme .btn-primary:hover {
    background: #FFFFFF;
    color: #101426;
}

/* ==========================================================================
   HERO SECTION
   ========================================================================== */
.main-wrapper {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px 60px;
}

.hero-section {
    display: grid;
    grid-template-columns: 1.15fr 0.85fr;
    align-items: center;
    gap: 48px;
    padding: 70px 0 60px;
}

.hero-tag {
    display: inline-block;
    color: var(--accent-coral);
    font-size: 0.95rem;
    font-weight: 700;
    letter-spacing: 1px;
    margin-bottom: 18px;
    text-transform: uppercase;
}

.hero-title {
    font-family: var(--font-heading);
    font-size: 3.4rem;
    line-height: 1.2;
    color: var(--text-heading);
    font-weight: 700;
    letter-spacing: -1px;
    margin-bottom: 24px;
}

.highlight-wrapper {
    position: relative;
    display: inline-block;
    white-space: nowrap;
}

.brush-underline {
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 100%;
    height: 16px;
    pointer-events: none;
}

.hero-desc {
    font-size: 1.05rem;
    color: var(--text-body);
    line-height: 1.7;
    max-width: 520px;
    margin-bottom: 36px;
}

.hero-cta-group {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 28px;
}

.btn-jadoo-primary {
    background: var(--accent-orange);
    color: #FFFFFF;
    padding: 15px 32px;
    border-radius: 10px;
    font-weight: 600;
    font-size: 1.05rem;
    box-shadow: var(--shadow-btn);
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
}

.btn-jadoo-primary:hover {
    background: #E09600;
    transform: translateY(-3px);
    box-shadow: 0px 20px 35px rgba(241, 165, 1, 0.4);
}

.btn-jadoo-demo {
    background: none;
    border: none;
    display: inline-flex;
    align-items: center;
    gap: 14px;
    cursor: pointer;
    color: var(--text-heading);
    font-family: var(--font-sans);
    font-size: 1rem;
    font-weight: 500;
    transition: var(--transition);
}

.play-btn-circle {
    width: 48px;
    height: 48px;
    background: var(--accent-coral);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #FFFFFF;
    box-shadow: var(--shadow-coral);
    transition: var(--transition);
}

.play-btn-circle svg {
    width: 16px;
    height: 16px;
    margin-left: 2px;
}

.btn-jadoo-demo:hover .play-btn-circle {
    transform: scale(1.1);
    box-shadow: 0px 20px 35px rgba(223, 105, 81, 0.45);
}

.btn-jadoo-demo:hover {
    color: var(--accent-coral);
}

/* Hero Visual Showcase */
.hero-visual {
    display: flex;
    justify-content: center;
    position: relative;
}

.hero-card-main {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 36px 30px;
    box-shadow: var(--shadow-card);
    border: 1px solid var(--border-color);
    position: relative;
    width: 100%;
    max-width: 380px;
    text-align: center;
    transition: var(--transition);
}

.hero-card-main:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
}

.student-badge-top {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(0, 176, 116, 0.1);
    color: var(--accent-green);
    font-size: 0.82rem;
    font-weight: 600;
    padding: 6px 14px;
    border-radius: var(--radius-full);
    margin-bottom: 24px;
}

.dot-status {
    width: 8px;
    height: 8px;
    background: var(--accent-green);
    border-radius: 50%;
    box-shadow: 0 0 8px var(--accent-green);
}

.student-avatar-large {
    margin-bottom: 20px;
}

.avatar-circle {
    width: 90px;
    height: 90px;
    margin: 0 auto;
    background: linear-gradient(135deg, #DF6951 0%, #F1A501 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #FFFFFF;
    font-size: 1.6rem;
    font-weight: 800;
    box-shadow: 0 10px 25px rgba(223, 105, 81, 0.35);
}

.student-details h3 {
    font-size: 1.4rem;
    color: var(--text-heading);
    font-weight: 700;
    margin-bottom: 6px;
}

.student-id-badge {
    font-size: 1rem;
    color: var(--accent-coral);
    font-weight: 600;
    margin-bottom: 6px;
}

.student-id-badge strong {
    letter-spacing: 0.5px;
}

.student-sub {
    font-size: 0.88rem;
    color: var(--text-muted);
}

/* Floating Mini Card */
.floating-mini-card {
    position: absolute;
    bottom: -20px;
    right: -25px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    box-shadow: 0px 15px 35px rgba(0, 0, 0, 0.1);
    border-radius: var(--radius-md);
    padding: 12px 18px;
    display: flex;
    align-items: center;
    gap: 12px;
    animation: floatCard 4s ease-in-out infinite alternate;
}

@keyframes floatCard {
    0% { transform: translateY(0px); }
    100% { transform: translateY(-8px); }
}

.mini-icon {
    font-size: 1.4rem;
}

.mini-info {
    text-align: left;
    display: flex;
    flex-direction: column;
}

.mini-title {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 500;
}

.mini-status {
    font-size: 0.85rem;
    color: var(--accent-green);
    font-weight: 700;
}

/* ==========================================================================
   ASSIGNMENTS SECTION
   ========================================================================== */
.assignments-section {
    padding: 60px 0 50px;
}

.text-center {
    text-align: center;
}

.sub-heading {
    display: block;
    color: var(--text-muted);
    font-size: 0.95rem;
    font-weight: 700;
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 8px;
}

.main-heading {
    font-family: var(--font-heading);
    font-size: 2.6rem;
    color: var(--text-heading);
    font-weight: 700;
    letter-spacing: -0.5px;
    margin-bottom: 48px;
}

.assignment-cards-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 36px;
    max-width: 960px;
    margin: 0 auto;
}

.assignment-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-card);
    padding: 28px;
    display: flex;
    flex-direction: column;
    transition: var(--transition);
    position: relative;
}

.assignment-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-hover);
}

.card-badge-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
}

.pill-badge {
    background: rgba(241, 165, 1, 0.15);
    color: #D98200;
    font-size: 0.8rem;
    font-weight: 700;
    padding: 4px 12px;
    border-radius: var(--radius-full);
}

.pill-badge.pill-purple {
    background: rgba(123, 97, 255, 0.12);
    color: var(--accent-purple);
}

.status-pill {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent-green);
    display: inline-flex;
    align-items: center;
}

.status-pill.done::before {
    content: '✓';
    margin-right: 4px;
    font-weight: bold;
}

.card-visual-box {
    background: linear-gradient(135deg, #FFF1DA 0%, #FFE5D9 100%);
    border-radius: var(--radius-md);
    padding: 30px 20px;
    text-align: center;
    margin-bottom: 22px;
    border: 1px solid rgba(241, 165, 1, 0.15);
}

body.dark-theme .card-visual-box {
    background: linear-gradient(135deg, rgba(241, 165, 1, 0.15) 0%, rgba(223, 105, 81, 0.15) 100%);
    border-color: rgba(255, 255, 255, 0.08);
}

.card-visual-box.visual-purple {
    background: linear-gradient(135deg, #EBE6FF 0%, #F5F3FF 100%);
    border-color: rgba(123, 97, 255, 0.15);
}

body.dark-theme .card-visual-box.visual-purple {
    background: linear-gradient(135deg, rgba(123, 97, 255, 0.15) 0%, rgba(79, 70, 229, 0.15) 100%);
}

.visual-inner .visual-tag {
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
    color: var(--accent-coral);
    margin-bottom: 4px;
}

.visual-purple .visual-tag {
    color: var(--accent-purple);
}

.visual-inner h4 {
    font-size: 1.25rem;
    color: var(--text-heading);
    font-weight: 700;
    margin-bottom: 4px;
}

.visual-inner p {
    font-size: 0.82rem;
    color: var(--text-body);
}

.card-body {
    flex: 1;
    margin-bottom: 24px;
}

.card-title {
    font-size: 1.2rem;
    color: var(--text-heading);
    font-weight: 700;
    margin-bottom: 10px;
}

.card-text {
    font-size: 0.92rem;
    color: var(--text-body);
    line-height: 1.6;
}

.card-footer-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.btn-card-open {
    background: var(--text-heading);
    color: #FFFFFF;
    padding: 11px 16px;
    border-radius: 10px;
    font-size: 0.9rem;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: var(--transition);
}

body.dark-theme .btn-card-open {
    background: #FFFFFF;
    color: #101426;
}

.btn-card-open:hover {
    background: var(--accent-coral);
    transform: translateY(-2px);
    box-shadow: var(--shadow-coral);
}

body.dark-theme .btn-card-open:hover {
    background: var(--accent-coral);
    color: #FFFFFF;
}

.btn-card-open svg {
    width: 16px;
    height: 16px;
}

.btn-card-preview {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-heading);
    padding: 11px 16px;
    border-radius: 10px;
    font-size: 0.9rem;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    cursor: pointer;
    font-family: var(--font-sans);
    transition: var(--transition);
}

.btn-card-preview:hover {
    border-color: var(--accent-orange);
    color: var(--accent-orange);
    background: rgba(241, 165, 1, 0.06);
    transform: translateY(-2px);
}

.btn-card-preview svg {
    width: 16px;
    height: 16px;
}

/* ==========================================================================
   MINIMAL INFO BANNER
   ========================================================================== */
.info-section {
    padding: 40px 0 20px;
}

.info-banner-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-card);
    padding: 36px 40px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 32px;
}

.info-text h3 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    color: var(--text-heading);
    font-weight: 700;
    margin-bottom: 16px;
}

.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px 32px;
}

.info-item {
    display: flex;
    flex-direction: column;
}

.info-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    font-weight: 500;
    margin-bottom: 2px;
}

.info-val {
    font-size: 1rem;
    color: var(--text-heading);
    font-weight: 600;
}

.info-val.highlight {
    color: var(--accent-coral);
}

.info-val.text-green {
    color: var(--accent-green);
}

.btn-jadoo-outline {
    border: 1.5px solid var(--border-color);
    color: var(--text-heading);
    padding: 12px 24px;
    border-radius: 10px;
    font-size: 0.95rem;
    font-weight: 600;
    transition: var(--transition);
    display: inline-block;
    white-space: nowrap;
}

.btn-jadoo-outline:hover {
    border-color: var(--accent-coral);
    color: var(--accent-coral);
    background: rgba(223, 105, 81, 0.05);
}

/* ==========================================================================
   FOOTER
   ========================================================================== */
.footer {
    border-top: 1px solid var(--border-color);
    padding: 30px 0;
    text-align: center;
}

.footer-container p {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* ==========================================================================
   MODAL LIVE PREVIEW (IFRAME)
   ========================================================================== */
.modal-backdrop {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(16, 20, 38, 0.75);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
}

.modal-backdrop.active {
    opacity: 1;
    pointer-events: auto;
}

.modal-container {
    background: var(--bg-card);
    width: 100%;
    max-width: 1100px;
    height: 85vh;
    border-radius: var(--radius-lg);
    box-shadow: 0 25px 70px rgba(0, 0, 0, 0.35);
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    transform: scale(0.95);
    transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.modal-backdrop.active .modal-container {
    transform: scale(1);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-subtle);
}

.modal-title-wrap {
    display: flex;
    align-items: center;
    gap: 10px;
}

.modal-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--accent-coral);
    box-shadow: 0 0 10px var(--accent-coral);
}

.modal-title-wrap h3 {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--text-heading);
}

.modal-controls {
    display: flex;
    align-items: center;
    gap: 10px;
}

.modal-btn {
    background: none;
    border: 1px solid var(--border-color);
    width: 36px;
    height: 36px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-heading);
    cursor: pointer;
    transition: var(--transition);
}

.modal-btn:hover {
    border-color: var(--accent-coral);
    color: var(--accent-coral);
    background: rgba(223, 105, 81, 0.08);
}

.modal-btn svg {
    width: 18px;
    height: 18px;
}

.modal-body {
    flex: 1;
    position: relative;
    background: #FFFFFF;
}

.modal-body iframe {
    width: 100%;
    height: 100%;
    border: none;
}

.iframe-loading {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--bg-card);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 16px;
    z-index: 10;
    transition: opacity 0.3s ease;
}

.iframe-loading.hidden {
    opacity: 0;
    pointer-events: none;
}

.spinner {
    width: 36px;
    height: 36px;
    border: 3px solid rgba(241, 165, 1, 0.2);
    border-top-color: var(--accent-orange);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ==========================================================================
   RESPONSIVE DESIGN
   ========================================================================== */
@media (max-width: 992px) {
    .hero-section {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
        padding-top: 40px;
    }

    .hero-desc {
        margin: 0 auto 32px;
    }

    .hero-cta-group {
        justify-content: center;
    }

    .hero-visual {
        order: -1;
    }

    .floating-mini-card {
        right: 0px;
    }

    .info-banner-card {
        flex-direction: column;
        text-align: center;
    }

    .info-grid {
        text-align: left;
    }
}

@media (max-width: 640px) {
    .hero-title {
        font-size: 2.3rem;
    }

    .main-heading {
        font-size: 2rem;
    }

    .assignment-cards-container {
        grid-template-columns: 1fr;
    }

    .card-footer-actions {
        grid-template-columns: 1fr;
    }

    .nav-menu {
        display: none;
    }

    .modal-container {
        height: 92vh;
        padding: 0;
    }
}