/* ============================================================
   MyCenterFlow Landing Page — landing.css
   ============================================================ */

/* Variables */
:root {
    --primary: #615DFF;
    --cyan: #3DD9EB;
    --dark: #2F3645;
    --gray: #6B7280;
    --gray-light: #F3F4F6;
    --border: #E5E7EB;
    --white: #FFFFFF;
    --gradient: linear-gradient(135deg, #615DFF 0%, #3DD9EB 100%);
    --gradient-soft: linear-gradient(135deg, rgba(97,93,255,0.08) 0%, rgba(61,217,235,0.08) 100%);
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
    --shadow-md: 0 4px 16px rgba(97,93,255,0.10), 0 2px 8px rgba(0,0,0,0.06);
    --shadow-lg: 0 16px 48px rgba(97,93,255,0.14), 0 4px 16px rgba(0,0,0,0.08);
    --radius: 12px;
    --radius-lg: 20px;
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html { scroll-behavior: smooth; font-size: 16px; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--dark);
    background: var(--white);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul { list-style: none; }

/* ============================================================
   Utility
   ============================================================ */
.container {
    width: 100%;
    max-width: 1160px;
    margin: 0 auto;
    padding: 0 24px;
}

.gradient-text {
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: 8px;
    font-size: 0.9375rem;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: transform var(--transition), box-shadow var(--transition), opacity var(--transition);
    letter-spacing: -0.01em;
}

.btn-primary {
    background: var(--gradient);
    color: var(--white);
    box-shadow: 0 4px 16px rgba(97,93,255,0.35);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(97,93,255,0.45);
}

.btn-primary:active { transform: translateY(0); }

.btn-secondary {
    background: transparent;
    color: var(--dark);
    border: 1.5px solid var(--border);
}

.btn-secondary:hover {
    border-color: var(--primary);
    color: var(--primary);
    transform: translateY(-1px);
}

/* ============================================================
   Animations
   ============================================================ */
@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50%       { transform: translateY(-12px); }
}

@keyframes gradientShift {
    0%   { background-position: 0% 50%; }
    50%  { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(28px); }
    to   { opacity: 1; transform: translateY(0); }
}

@keyframes checkmark {
    0%   { stroke-dashoffset: 100; }
    100% { stroke-dashoffset: 0; }
}

@keyframes scaleIn {
    from { transform: scale(0.8); opacity: 0; }
    to   { transform: scale(1); opacity: 1; }
}

.fade-in-up {
    opacity: 0;
    transform: translateY(28px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================================
   Navbar
   ============================================================ */
.landing-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: 16px 0;
    background: rgba(255,255,255,0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid transparent;
    transition: border-color var(--transition), box-shadow var(--transition);
}

.landing-nav.scrolled {
    border-bottom-color: var(--border);
    box-shadow: var(--shadow-sm);
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo img {
    height: 32px;
    width: auto;
}

.nav-logo-text {
    font-size: 1.125rem;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.nav-links a {
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--gray);
    transition: color var(--transition);
}

.nav-links a:hover { color: var(--dark); }

.nav-links a.btn-primary,
.nav-links a.btn-primary:hover {
    color: var(--white);
}

.nav-cta { margin-left: 16px; }

.nav-hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 4px;
    background: none;
    border: none;
}

.nav-hamburger span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--dark);
    border-radius: 2px;
    transition: transform var(--transition), opacity var(--transition);
}

.nav-hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-hamburger.open span:nth-child(2) { opacity: 0; }
.nav-hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.nav-mobile {
    display: none;
    flex-direction: column;
    gap: 0;
    background: var(--white);
    border-top: 1px solid var(--border);
    padding: 16px 24px 24px;
}

.nav-mobile.open { display: flex; }

.nav-mobile a {
    padding: 12px 0;
    font-size: 1rem;
    font-weight: 500;
    color: var(--dark);
    border-bottom: 1px solid var(--gray-light);
}

.nav-mobile a:last-child { border-bottom: none; }

/* ============================================================
   Hero
   ============================================================ */
.hero {
    padding: 140px 0 100px;
    background: linear-gradient(160deg, #FAFAFF 0%, #F0F9FF 60%, #FAFAFF 100%);
    overflow: hidden;
    position: relative;
}

.hero::before {
    content: '';
    position: absolute;
    top: -200px;
    right: -200px;
    width: 700px;
    height: 700px;
    background: radial-gradient(circle, rgba(97,93,255,0.06) 0%, transparent 70%);
    pointer-events: none;
}

.hero-inner {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(97,93,255,0.08);
    border: 1px solid rgba(97,93,255,0.18);
    border-radius: 100px;
    padding: 6px 14px;
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 24px;
}

.hero-badge-dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--primary);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50%       { opacity: 0.4; }
}

.hero h1 {
    font-size: clamp(2.25rem, 4vw, 3.25rem);
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.03em;
    color: var(--dark);
    margin-bottom: 24px;
}

.hero-desc {
    font-size: 1.0625rem;
    color: var(--gray);
    line-height: 1.75;
    max-width: 480px;
    margin-bottom: 40px;
}

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

/* Dashboard Mockup */
.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.dashboard-mockup {
    background: var(--white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 20px;
    width: 100%;
    max-width: 480px;
    animation: float 5s ease-in-out infinite;
    border: 1px solid var(--border);
}

.mockup-topbar {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 16px;
}

.mockup-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
}

.mockup-dot.red   { background: #FF5F57; }
.mockup-dot.amber { background: #FEBC2E; }
.mockup-dot.green { background: #28C840; }

.mockup-title-bar {
    flex: 1;
    height: 10px;
    background: var(--gray-light);
    border-radius: 6px;
    margin-left: 8px;
}

.mockup-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin-bottom: 14px;
}

.mockup-stat {
    background: var(--gradient-soft);
    border-radius: var(--radius);
    padding: 12px;
    border: 1px solid rgba(97,93,255,0.10);
}

.mockup-stat-label {
    font-size: 0.6875rem;
    font-weight: 600;
    color: var(--gray);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 6px;
}

.mockup-stat-value {
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--dark);
}

.mockup-stat-value.good  { color: #10B981; }
.mockup-stat-value.warn  { color: #F59E0B; }
.mockup-stat-value.crit  { color: #EF4444; }

.mockup-section-title {
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--gray);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin: 14px 0 8px;
}

.mockup-classrooms {
    display: flex;
    flex-direction: column;
    gap: 7px;
}

.mockup-classroom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 12px;
    background: var(--gray-light);
    border-radius: 8px;
}

.mockup-classroom-name {
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--dark);
}

.mockup-ratio {
    font-size: 0.75rem;
    font-weight: 600;
    padding: 3px 8px;
    border-radius: 100px;
}

.ratio-ok      { background: rgba(16,185,129,0.12); color: #059669; }
.ratio-warn    { background: rgba(245,158,11,0.12);  color: #D97706; }
.ratio-alert   { background: rgba(239,68,68,0.12);   color: #DC2626; }

.mockup-alerts {
    margin-top: 14px;
    display: flex;
    flex-direction: column;
    gap: 7px;
}

.mockup-alert {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 12px;
    border-radius: 8px;
    font-size: 0.8125rem;
    font-weight: 500;
}

.mockup-alert.warn {
    background: rgba(245,158,11,0.08);
    border: 1px solid rgba(245,158,11,0.20);
    color: #92400E;
}

.mockup-alert.info {
    background: rgba(97,93,255,0.06);
    border: 1px solid rgba(97,93,255,0.15);
    color: var(--primary);
}

.mockup-alert-icon { font-size: 0.875rem; }

/* ============================================================
   Section: Problem
   ============================================================ */
.section-problem {
    padding: 100px 0;
    background: var(--white);
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-label {
    display: inline-block;
    font-size: 0.8125rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--primary);
    margin-bottom: 12px;
}

.section-header h2 {
    font-size: clamp(1.75rem, 3vw, 2.5rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    color: var(--dark);
    max-width: 600px;
    margin: 0 auto 16px;
    line-height: 1.2;
}

.section-header p {
    font-size: 1.0625rem;
    color: var(--gray);
    max-width: 520px;
    margin: 0 auto;
}

.cards-grid-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px 24px;
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: rgba(97,93,255,0.20);
}

.card-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: var(--gradient-soft);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
    font-size: 1.375rem;
}

.card h3 {
    font-size: 1rem;
    font-weight: 700;
    color: var(--dark);
    margin-bottom: 10px;
    letter-spacing: -0.01em;
}

.card p {
    font-size: 0.9rem;
    color: var(--gray);
    line-height: 1.65;
}

/* ============================================================
   Section: Features
   ============================================================ */
.section-features {
    padding: 100px 0;
    background: linear-gradient(180deg, #F9FAFE 0%, #FFFFFF 100%);
}

.cards-grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.feature-card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 32px 28px;
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: rgba(97,93,255,0.20);
}

.feature-card .card-icon {
    background: var(--gradient);
    color: var(--white);
    font-size: 1.25rem;
}

/* ============================================================
   Section: How It Works
   ============================================================ */
.section-how {
    padding: 100px 0;
    background: var(--white);
}

.steps-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    position: relative;
}

.steps-grid::before {
    content: '';
    position: absolute;
    top: 36px;
    left: calc(16.66% + 28px);
    right: calc(16.66% + 28px);
    height: 2px;
    background: linear-gradient(90deg, var(--primary), var(--cyan));
    opacity: 0.3;
    z-index: 0;
}

.step {
    text-align: center;
    position: relative;
    z-index: 1;
}

.step-number {
    width: 72px;
    height: 72px;
    border-radius: 50%;
    background: var(--gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--white);
    margin: 0 auto 24px;
    box-shadow: 0 8px 24px rgba(97,93,255,0.30);
}

.step-icon { font-size: 1.75rem; }

.step h3 {
    font-size: 1.0625rem;
    font-weight: 700;
    color: var(--dark);
    margin-bottom: 10px;
    letter-spacing: -0.01em;
}

.step p {
    font-size: 0.9375rem;
    color: var(--gray);
    line-height: 1.65;
}

/* ============================================================
   Section: CTA + Early Access Form
   ============================================================ */
.section-cta {
    padding: 100px 0;
    background: linear-gradient(160deg, #F5F4FF 0%, #F0FAFE 100%);
    position: relative;
    overflow: hidden;
}

.section-cta::before {
    content: '';
    position: absolute;
    top: -150px;
    left: -150px;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(97,93,255,0.07) 0%, transparent 70%);
    pointer-events: none;
}

.cta-header {
    text-align: center;
    margin-bottom: 56px;
}

.cta-header h2 {
    font-size: clamp(1.875rem, 3.5vw, 2.75rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    color: var(--dark);
    max-width: 640px;
    margin: 0 auto 16px;
    line-height: 1.2;
}

.cta-header p {
    font-size: 1.0625rem;
    color: var(--gray);
    max-width: 540px;
    margin: 0 auto;
    line-height: 1.75;
}

/* Form Card */
.form-card {
    background: var(--white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 48px;
    max-width: 680px;
    margin: 0 auto;
    border: 1px solid rgba(97,93,255,0.10);
    position: relative;
}

.form-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.form-group.full { grid-column: 1 / -1; }

.form-group label {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--dark);
}

.form-group label .required-star { color: var(--primary); margin-left: 2px; }

.form-group input,
.form-group select {
    padding: 11px 14px;
    border: 1.5px solid var(--border);
    border-radius: 8px;
    font-size: 0.9375rem;
    font-family: inherit;
    color: var(--dark);
    background: var(--white);
    transition: border-color var(--transition), box-shadow var(--transition);
    outline: none;
    appearance: none;
    -webkit-appearance: none;
}

.form-group input::placeholder { color: #9CA3AF; }

.form-group input:focus,
.form-group select:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(97,93,255,0.12);
}

.form-group input.error,
.form-group select.error {
    border-color: #EF4444;
    box-shadow: 0 0 0 3px rgba(239,68,68,0.10);
}

.field-error {
    font-size: 0.8125rem;
    color: #EF4444;
    font-weight: 500;
    display: none;
}

.field-error.visible { display: block; }

.select-wrapper {
    position: relative;
}

.select-wrapper::after {
    content: '▾';
    position: absolute;
    right: 14px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--gray);
    pointer-events: none;
    font-size: 0.875rem;
}

.form-submit-row {
    margin-top: 28px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
}

.btn-submit {
    width: 100%;
    justify-content: center;
    padding: 14px 28px;
    font-size: 1rem;
}

.form-note {
    font-size: 0.8125rem;
    color: var(--gray);
    text-align: center;
}

/* API error banner */
.form-error-banner {
    display: none;
    align-items: center;
    gap: 10px;
    background: rgba(239,68,68,0.07);
    border: 1px solid rgba(239,68,68,0.20);
    border-radius: 8px;
    padding: 12px 16px;
    font-size: 0.9rem;
    color: #991B1B;
    margin-bottom: 20px;
    font-weight: 500;
}

.form-error-banner.visible { display: flex; }
.form-error-banner-icon { font-size: 1rem; flex-shrink: 0; }

/* Spinner */
.btn-spinner {
    display: none;
    width: 18px;
    height: 18px;
    border: 2px solid rgba(255,255,255,0.4);
    border-top-color: var(--white);
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
}

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

.btn-submit.loading .btn-text { display: none; }
.btn-submit.loading .btn-spinner { display: block; }

/* Success State */
.form-success {
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 24px 0;
    animation: scaleIn 0.4s ease;
}

.form-success.visible { display: flex; }
.form-success-icon { font-size: 3.5rem; margin-bottom: 16px; }

.form-success h3 {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--dark);
    margin-bottom: 10px;
    letter-spacing: -0.02em;
}

.form-success p {
    font-size: 1rem;
    color: var(--gray);
    line-height: 1.7;
    max-width: 400px;
}

/* ============================================================
   Footer
   ============================================================ */
.landing-footer {
    padding: 48px 0 32px;
    background: var(--dark);
    color: rgba(255,255,255,0.7);
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 24px;
    padding-bottom: 24px;
    border-bottom: 1px solid rgba(255,255,255,0.08);
    margin-bottom: 24px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.footer-logo img { height: 28px; }

.footer-logo-text {
    font-size: 1.0625rem;
    font-weight: 700;
    color: var(--white);
}

.footer-links {
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
}

.footer-links a {
    font-size: 0.875rem;
    color: rgba(255,255,255,0.6);
    transition: color var(--transition);
}

.footer-links a:hover { color: var(--white); }

.footer-social {
    display: flex;
    gap: 14px;
}

.footer-social a {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: rgba(255,255,255,0.08);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.875rem;
    color: rgba(255,255,255,0.7);
    transition: background var(--transition), color var(--transition);
}

.footer-social a:hover {
    background: var(--primary);
    color: var(--white);
}

.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
}

.footer-copy {
    font-size: 0.8125rem;
    color: rgba(255,255,255,0.45);
}

/* ============================================================
   Responsive
   ============================================================ */
@@media (max-width: 1024px) {
    .cards-grid-4 { grid-template-columns: repeat(2, 1fr); }
    .hero-inner   { gap: 40px; }
}

@@media (max-width: 768px) {
    .nav-links { display: none; }
    .nav-hamburger { display: flex; }

    .hero {
        padding: 100px 0 60px;
    }

    .hero-inner {
        grid-template-columns: 1fr;
        gap: 48px;
    }

    .hero-desc { max-width: 100%; }

    .cards-grid-4 { grid-template-columns: 1fr; }
    .cards-grid-3 { grid-template-columns: 1fr; }

    .steps-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .steps-grid::before { display: none; }

    .form-card { padding: 32px 24px; }
    .form-grid { grid-template-columns: 1fr; }
    .form-group.full { grid-column: 1; }

    .footer-inner {
        flex-direction: column;
        align-items: flex-start;
    }
}

@@media (max-width: 480px) {
    .hero h1 { font-size: 2rem; }
    .hero-actions { flex-direction: column; align-items: stretch; }
    .hero-actions .btn { justify-content: center; }
    .dashboard-mockup { padding: 16px; }
}