/* =========================================================
   NOUN Exam Summary Hub — Design System
   Academic, clean, mobile-first. Primary: dark green + white.
   ========================================================= */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');

:root {
  --green-900: #003d00;
  --green-700: #004d00;
  --green: #006400;
  --green-600: #00791a;
  --green-100: #e6f2e6;
  --green-50: #f2f8f2;
  --white: #ffffff;
  --gray-50: #f7f8f7;
  --gray-100: #eef0ee;
  --gray-200: #e0e3e0;
  --gray-400: #9aa39a;
  --gray-600: #5b635b;
  --gray-800: #24291f;
  --text: #1a1f16;
  --danger: #b3261e;
  --danger-bg: #fdecea;
  --warning: #8a6d00;
  --warning-bg: #fff8e1;
  --success: #0f7a32;
  --success-bg: #e7f7ec;
  --radius-sm: 8px;
  --radius: 14px;
  --radius-lg: 20px;
  --shadow-sm: 0 1px 3px rgba(0, 30, 0, 0.06);
  --shadow: 0 4px 16px rgba(0, 30, 0, 0.08);
  --shadow-lg: 0 12px 32px rgba(0, 30, 0, 0.14);
  --header-h: 64px;
  --max-w: 1180px;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: var(--text);
  background: var(--gray-50);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; }
h1, h2, h3, h4 { line-height: 1.2; margin: 0 0 .5em; font-weight: 800; letter-spacing: -0.01em; }
p { margin: 0 0 1em; color: var(--gray-600); }

.container { max-width: var(--max-w); margin: 0 auto; padding: 0 20px; }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }

/* ---------------- Buttons ---------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 22px; border-radius: 999px; border: none; cursor: pointer;
  font-weight: 600; font-size: 0.95rem; transition: transform .12s ease, box-shadow .12s ease, background .15s ease;
  white-space: nowrap;
}
.btn:active { transform: scale(0.97); }
.btn:disabled { opacity: 0.6; cursor: not-allowed; transform: none; }
.btn--primary { background: var(--green); color: var(--white); box-shadow: var(--shadow-sm); }
.btn--primary:hover:not(:disabled) { background: var(--green-700); box-shadow: var(--shadow); }
.btn--outline { background: transparent; color: var(--green); border: 1.5px solid var(--green); }
.btn--outline:hover:not(:disabled) { background: var(--green-50); }
.btn--ghost { background: transparent; color: var(--gray-600); }
.btn--ghost:hover:not(:disabled) { background: var(--gray-100); }
.btn--danger { background: var(--danger); color: var(--white); }
.btn--success { background: var(--success); color: var(--white); }
.btn--small { padding: 8px 16px; font-size: 0.85rem; }
.btn--block { width: 100%; }

.google-signup-btn {
  width: 100%; min-height: 48px; display: inline-flex; align-items: center; justify-content: center; gap: 12px;
  padding: 10px 16px; border: 1px solid #dadce0; border-radius: 4px; background: var(--white); color: #3c4043;
  cursor: pointer; font-size: 0.95rem; font-weight: 600; box-shadow: 0 1px 2px rgba(60,64,67,0.15);
  transition: background .15s ease, box-shadow .15s ease, border-color .15s ease;
}
.google-signup-btn:hover:not(:disabled) { background: #f8fafd; border-color: #c8cdd1; box-shadow: 0 1px 3px rgba(60,64,67,0.25); }
.google-signup-btn:focus-visible { outline: 3px solid rgba(66,133,244,0.35); outline-offset: 2px; }
.google-signup-btn:disabled { opacity: 0.6; cursor: not-allowed; }
.google-signup-btn__icon { width: 20px; height: 20px; flex: 0 0 20px; }
.google-signup-btn .spinner { border-color: rgba(60,64,67,0.25); border-top-color: #4285f4; }
.auth-divider { display: flex; align-items: center; gap: 12px; margin: 16px 0; color: var(--gray-400); font-size: 0.82rem; }
.auth-divider::before, .auth-divider::after { content: ""; height: 1px; flex: 1; background: var(--gray-200); }

.spinner {
  width: 14px; height: 14px; border-radius: 50%;
  border: 2px solid rgba(255,255,255,0.5); border-top-color: #fff;
  display: inline-block; animation: spin .7s linear infinite;
}
.btn--outline .spinner, .btn--ghost .spinner { border-color: rgba(0,100,0,0.3); border-top-color: var(--green); }
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------------- Header ---------------- */
.site-header {
  position: sticky; top: 0; z-index: 100; background: var(--white);
  border-bottom: 1px solid var(--gray-100); height: var(--header-h);
}
.header__inner { height: var(--header-h); display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 1.05rem; color: var(--green-900); }
.brand__logo { border-radius: 8px; }
.brand__logo--small { border-radius: 6px; }

.nav-toggle {
  display: flex; flex-direction: column; justify-content: center; gap: 4px;
  width: 40px; height: 40px; background: none; border: none; cursor: pointer; border-radius: 8px;
}
.nav-toggle span { width: 22px; height: 2px; background: var(--gray-800); border-radius: 2px; transition: .2s; }
.nav-toggle:hover { background: var(--gray-100); }

.primary-nav {
  position: fixed; top: var(--header-h); left: 0; right: 0; bottom: 0;
  background: var(--white); display: flex; flex-direction: column; padding: 20px;
  gap: 4px; transform: translateX(100%); transition: transform .25s ease; overflow-y: auto;
}
.primary-nav--open { transform: translateX(0); }
.nav-link { padding: 14px 12px; border-radius: var(--radius-sm); font-weight: 600; color: var(--gray-800); }
.nav-link:hover { background: var(--green-50); color: var(--green-900); }
.nav-link--admin { color: var(--green-700); }

@media (min-width: 900px) {
  .nav-toggle { display: none; }
  .primary-nav {
    position: static; transform: none; flex-direction: row; align-items: center; padding: 0;
    width: auto; background: none;
  }
  .nav-link { padding: 8px 10px; }
}

/* ---------------- Hero ---------------- */
.hero {
  background: linear-gradient(180deg, var(--green-50) 0%, var(--gray-50) 100%);
  padding: 56px 0 40px;
  text-align: center;
}
.hero__eyebrow {
  display: inline-block; background: var(--green-100); color: var(--green-900);
  padding: 6px 14px; border-radius: 999px; font-weight: 700; font-size: 0.78rem; letter-spacing: .04em;
  text-transform: uppercase; margin-bottom: 18px;
}
.hero h1 { font-size: clamp(1.8rem, 5vw, 2.9rem); color: var(--gray-800); max-width: 760px; margin: 0 auto 14px; }
.hero__sub { max-width: 560px; margin: 0 auto 28px; font-size: 1.02rem; }
.hero__actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; margin-bottom: 30px; }

/* ---------------- Search ---------------- */
.search-box {
  display: flex; align-items: center; gap: 8px; background: var(--white);
  border: 1.5px solid var(--gray-200); border-radius: 999px; padding: 6px 6px 6px 20px;
  max-width: 560px; margin: 0 auto; box-shadow: var(--shadow-sm);
}
.search-box input {
  flex: 1; border: none; outline: none; font-size: 1rem; padding: 10px 0; font-family: inherit; background: transparent;
}
.search-box .btn { flex-shrink: 0; }

/* ---------------- Sections ---------------- */
.section { padding: 44px 0; }
.section__head { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; margin-bottom: 22px; flex-wrap: wrap; }
.section__head h2 { font-size: 1.5rem; color: var(--gray-800); }

/* ---------------- Course Grid / Cards ---------------- */
.course-grid { display: grid; grid-template-columns: 1fr; gap: 16px; }
@media (min-width: 620px) { .course-grid { grid-template-columns: 1fr 1fr; } }
@media (min-width: 980px) { .course-grid { grid-template-columns: 1fr 1fr 1fr; } }
.course-grid--preview {
  display: flex; overflow-x: auto; gap: 16px; padding-bottom: 16px;
  scrollbar-color: var(--green) var(--gray-100); scrollbar-width: auto;
}
.course-grid--preview .course-card { flex: 0 0 min(300px, calc(100vw - 56px)); }
.course-grid__more { display: flex; justify-content: center; margin-top: 22px; }

.faq-list { display: flex; flex-direction: column; gap: 12px; max-width: 820px; margin: 0 auto; }
.faq-item { background: var(--white); border: 1px solid var(--gray-100); border-radius: var(--radius); box-shadow: var(--shadow-sm); }
.faq-item summary { cursor: pointer; padding: 18px 20px; font-weight: 700; color: var(--gray-800); list-style-position: inside; }
.faq-item summary::marker { color: var(--green); }
.faq-item p { padding: 0 20px 18px 38px; margin: 0; }

.card {
  background: var(--white); border-radius: var(--radius); padding: 20px;
  box-shadow: var(--shadow-sm); border: 1px solid var(--gray-100);
  transition: box-shadow .15s ease, transform .15s ease;
}
.card:hover { box-shadow: var(--shadow); }

.course-card { display: flex; flex-direction: column; gap: 10px; }
.course-card__top { display: flex; align-items: flex-start; justify-content: space-between; gap: 8px; }
.course-card__code { font-weight: 800; color: var(--green-900); font-size: 1.05rem; }
.badge {
  display: inline-flex; align-items: center; gap: 4px; font-size: 0.72rem; font-weight: 700;
  padding: 4px 10px; border-radius: 999px; letter-spacing: .02em; text-transform: uppercase;
}
.badge--free { background: var(--success-bg); color: var(--success); }
.badge--premium { background: #fff3d6; color: #8a6d00; }
.badge--locked { background: var(--gray-100); color: var(--gray-600); }
.course-card__name { font-weight: 600; color: var(--text); margin: 0; }
.course-card__actions { margin-top: auto; padding-top: 6px; }

.empty-state { text-align: center; padding: 48px 20px; color: var(--gray-600); }
.empty-state__icon { font-size: 2.4rem; margin-bottom: 10px; }

.skeleton { background: linear-gradient(90deg, var(--gray-100) 25%, var(--gray-50) 37%, var(--gray-100) 63%); background-size: 400% 100%; animation: shimmer 1.4s ease infinite; border-radius: var(--radius); height: 150px; }
@keyframes shimmer { 0% { background-position: 100% 50%; } 100% { background-position: 0 50%; } }

/* ---------------- Forms ---------------- */
.form { display: flex; flex-direction: column; gap: 16px; max-width: 440px; }
.field { display: flex; flex-direction: column; gap: 6px; }
.field label { font-weight: 600; font-size: 0.9rem; color: var(--gray-800); }
.field input, .field select, .field textarea {
  padding: 12px 14px; border-radius: var(--radius-sm); border: 1.5px solid var(--gray-200);
  font-size: 0.98rem; font-family: inherit; outline: none; background: var(--white); color: var(--text);
  transition: border-color .15s ease;
}
.field input:focus, .field select:focus, .field textarea:focus { border-color: var(--green); }
.field small { color: var(--gray-400); font-size: 0.8rem; }
.field--error input { border-color: var(--danger); }
.field__error { color: var(--danger); font-size: 0.82rem; }

.toggle-row { display: flex; align-items: center; justify-content: space-between; padding: 12px 14px; border: 1.5px solid var(--gray-200); border-radius: var(--radius-sm); }
.switch { position: relative; display: inline-block; width: 44px; height: 24px; flex-shrink: 0; }
.switch input { opacity: 0; width: 0; height: 0; }
.switch__track { position: absolute; inset: 0; background: var(--gray-200); border-radius: 999px; cursor: pointer; transition: .2s; }
.switch__track::before { content: ""; position: absolute; width: 18px; height: 18px; left: 3px; top: 3px; background: white; border-radius: 50%; transition: .2s; box-shadow: var(--shadow-sm); }
.switch input:checked + .switch__track { background: var(--green); }
.switch input:checked + .switch__track::before { transform: translateX(20px); }

.auth-card { max-width: 440px; margin: 60px auto; padding: 32px; }
.auth-card h1 { font-size: 1.5rem; text-align: center; }
.auth-card__foot { text-align: center; margin-top: 14px; font-size: 0.92rem; }

.alert { padding: 12px 16px; border-radius: var(--radius-sm); font-size: 0.9rem; margin-bottom: 4px; }
.alert--error { background: var(--danger-bg); color: var(--danger); }
.alert--success { background: var(--success-bg); color: var(--success); }
.alert--warning { background: var(--warning-bg); color: var(--warning); }
.alert--info { background: var(--green-50); color: var(--green-900); }

/* ---------------- Course Page ---------------- */
.course-hero { background: var(--white); border-bottom: 1px solid var(--gray-100); padding: 32px 0; }
.course-hero__meta { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; margin-bottom: 8px; }
.course-hero h1 { font-size: 1.6rem; margin-bottom: 6px; }

.pricing-grid { display: grid; grid-template-columns: 1fr; gap: 14px; }
@media (min-width: 720px) { .pricing-grid { grid-template-columns: 1fr 1fr 1fr; } }
.price-card { display: flex; flex-direction: column; gap: 10px; text-align: center; align-items: center; }
.price-card__amount { font-size: 1.7rem; font-weight: 800; color: var(--green-900); }
.price-card__label { font-weight: 600; }
.price-card__desc { font-size: 0.85rem; }

.pdf-preview { position: relative; background: var(--gray-100); border-radius: var(--radius); padding: 16px; display: flex; flex-direction: column; align-items: center; gap: 12px; overflow: hidden; }
.pdf-preview__page { max-width: 100%; height: auto; border-radius: 6px; box-shadow: var(--shadow-sm); }
.pdf-preview__page--blurred { filter: blur(6px) grayscale(15%); }
.pdf-preview__lock-overlay {
  position: absolute; inset: 0; display: flex; align-items: center; justify-content: center;
  background: rgba(255,255,255,0.15);
}
.pdf-preview__lock-badge {
  background: rgba(0, 61, 0, 0.92); color: white; padding: 14px 22px; border-radius: 999px;
  font-weight: 700; font-size: 0.9rem; display: flex; align-items: center; gap: 8px; box-shadow: var(--shadow-lg);
  text-align: center; max-width: 280px;
}
.pdf-preview__loading, .pdf-preview__error { color: var(--gray-600); padding: 30px; text-align: center; }
.pdf-preview__more { font-size: 0.85rem; color: var(--gray-600); }

.transfer-details { background: var(--green-50); border-radius: var(--radius-sm); padding: 16px; font-size: 0.92rem; }
.transfer-details dt { font-weight: 700; color: var(--green-900); margin-top: 8px; }
.transfer-details dd { margin: 0 0 4px; }

.upload-drop {
  border: 2px dashed var(--gray-200); border-radius: var(--radius-sm); padding: 24px; text-align: center;
  cursor: pointer; transition: border-color .15s ease; background: var(--white);
}
.upload-drop:hover { border-color: var(--green); }
.upload-drop input { display: none; }
.upload-drop__filename { font-weight: 600; color: var(--green-900); margin-top: 8px; }

.progress-bar { height: 8px; border-radius: 999px; background: var(--gray-100); overflow: hidden; }
.progress-bar__fill { height: 100%; background: var(--green); transition: width .2s ease; border-radius: 999px; }

/* ---------------- Tabs (Admin) ---------------- */
.tabs { display: flex; gap: 6px; overflow-x: auto; border-bottom: 1px solid var(--gray-100); margin-bottom: 24px; }
.tab-btn { padding: 12px 18px; border: none; background: none; font-weight: 700; color: var(--gray-600); cursor: pointer; white-space: nowrap; border-bottom: 3px solid transparent; }
.tab-btn.active { color: var(--green-900); border-color: var(--green); }
.tab-panel { display: none; }
.tab-panel.active { display: block; }

/* ---------------- Table ---------------- */
.table-wrap { overflow-x: auto; background: var(--white); border-radius: var(--radius); border: 1px solid var(--gray-100); }
table { width: 100%; border-collapse: collapse; min-width: 760px; }
th, td { padding: 12px 14px; text-align: left; font-size: 0.88rem; border-bottom: 1px solid var(--gray-100); white-space: nowrap; }
th { background: var(--gray-50); color: var(--gray-600); font-weight: 700; text-transform: uppercase; font-size: 0.72rem; letter-spacing: .03em; }
tr:last-child td { border-bottom: none; }
.status-pill { padding: 4px 10px; border-radius: 999px; font-size: 0.72rem; font-weight: 700; text-transform: capitalize; }
.status-pill--pending, .status-pill--pending_verification { background: var(--warning-bg); color: var(--warning); }
.status-pill--approved { background: var(--success-bg); color: var(--success); }
.status-pill--rejected { background: var(--danger-bg); color: var(--danger); }

.filter-row { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 16px; }
.filter-chip { padding: 8px 14px; border-radius: 999px; border: 1.5px solid var(--gray-200); background: var(--white); font-size: 0.82rem; font-weight: 600; cursor: pointer; color: var(--gray-600); }
.filter-chip.active { background: var(--green); border-color: var(--green); color: white; }

/* ---------------- Modal ---------------- */
.modal-backdrop { position: fixed; inset: 0; background: rgba(0,20,0,0.45); display: none; align-items: center; justify-content: center; z-index: 200; padding: 20px; }
.modal-backdrop.open { display: flex; }
.modal { background: white; border-radius: var(--radius-lg); padding: 24px; max-width: 480px; width: 100%; box-shadow: var(--shadow-lg); max-height: 90vh; overflow-y: auto; }
.modal__actions { display: flex; gap: 10px; justify-content: flex-end; margin-top: 18px; }
.modal img { border-radius: var(--radius-sm); }

/* ---------------- Toasts ---------------- */
#toast-container { position: fixed; bottom: 20px; left: 50%; transform: translateX(-50%); z-index: 300; display: flex; flex-direction: column; gap: 8px; width: min(92vw, 380px); }
.toast {
  background: var(--gray-800); color: white; padding: 13px 18px; border-radius: var(--radius-sm);
  font-size: 0.9rem; box-shadow: var(--shadow-lg); opacity: 0; transform: translateY(10px); transition: .25s ease;
}
.toast--show { opacity: 1; transform: translateY(0); }
.toast--success { background: var(--green-700); }
.toast--error { background: var(--danger); }
.toast--info { background: var(--gray-800); }

/* ---------------- Footer ---------------- */
.site-footer { background: var(--green-900); color: rgba(255,255,255,0.85); padding: 36px 0 26px; margin-top: 60px; }
.footer__inner { text-align: center; display: flex; flex-direction: column; align-items: center; gap: 6px; }
.footer__brand { display: flex; align-items: center; gap: 8px; font-weight: 700; color: white; margin-bottom: 6px; }
.footer__tagline { color: rgba(255,255,255,0.75); margin: 0; font-weight: 600; }
.footer__disclaimer { font-size: 0.8rem; color: rgba(255,255,255,0.55); max-width: 480px; }
.footer__copy { font-size: 0.78rem; color: rgba(255,255,255,0.4); margin-top: 6px; }

/* ---------------- Utility ---------------- */
.stack { display: flex; flex-direction: column; gap: 12px; }
.row { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.muted { color: var(--gray-400); font-size: 0.85rem; }
.divider { height: 1px; background: var(--gray-100); margin: 20px 0; border: none; }
.whatsapp-btn { position: fixed; bottom: 18px; right: 18px; z-index: 90; box-shadow: var(--shadow-lg); }

/* Payment modal */
.modal-backdrop.is-open { display: flex; }