:root {
  --bg: #f4f5fb;
  --bg-accent: radial-gradient(1200px 600px at 10% -10%, #e4e7ff 0%, transparent 60%),
               radial-gradient(900px 500px at 110% 10%, #f3e8ff 0%, transparent 55%);
  --surface: #ffffff;
  --surface-2: #f7f8fc;
  --surface-3: #eef0f8;
  --text: #0f172a;
  --text-muted: #64748b;
  --border: #e3e6f0;
  --border-strong: #cfd4e3;
  --primary: #4f46e5;
  --primary-2: #7c3aed;
  --primary-hover: #4338ca;
  --primary-soft: #eef0ff;
  --primary-text: #ffffff;
  --success: #059669;
  --success-soft: #e7f8f1;
  --danger: #dc2626;
  --danger-soft: #fdecec;
  --warning: #d97706;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, .06);
  --shadow: 0 1px 3px rgba(15, 23, 42, .06), 0 8px 24px rgba(15, 23, 42, .06);
  --shadow-lg: 0 20px 50px rgba(30, 27, 75, .12);
  --radius: 14px;
  --radius-sm: 10px;
  --ring: 0 0 0 4px rgba(79, 70, 229, .15);
}

[data-theme="dark"] {
  --bg: #0b0d17;
  --bg-accent: radial-gradient(1200px 600px at 10% -10%, rgba(79, 70, 229, .18) 0%, transparent 60%),
               radial-gradient(900px 500px at 110% 10%, rgba(124, 58, 237, .14) 0%, transparent 55%);
  --surface: #131625;
  --surface-2: #181c2e;
  --surface-3: #1f2438;
  --text: #e6e8f2;
  --text-muted: #9097b1;
  --border: #262b42;
  --border-strong: #343a56;
  --primary: #818cf8;
  --primary-2: #a78bfa;
  --primary-hover: #9aa3fb;
  --primary-soft: rgba(129, 140, 248, .14);
  --primary-text: #0b0d17;
  --success: #34d399;
  --success-soft: rgba(52, 211, 153, .12);
  --danger: #f87171;
  --danger-soft: rgba(248, 113, 113, .12);
  --warning: #fbbf24;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, .4);
  --shadow: 0 1px 3px rgba(0, 0, 0, .4), 0 8px 24px rgba(0, 0, 0, .25);
  --shadow-lg: 0 20px 50px rgba(0, 0, 0, .45);
  --ring: 0 0 0 4px rgba(129, 140, 248, .22);
}

* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, Arial, sans-serif;
  background: var(--bg-accent), var(--bg);
  background-attachment: fixed;
  color: var(--text);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  line-height: 1.5;
}

h1, h2, h3 { margin: 0; letter-spacing: -0.02em; }
h1 { font-size: 28px; font-weight: 800; }
h2 { font-size: 18px; font-weight: 700; }
h3 { font-size: 15px; font-weight: 700; }
p { margin: 0; }
.muted { color: var(--text-muted); }
.hidden { display: none !important; }

/* ---------- Form controls ---------- */
label { display: block; margin: 0 0 6px; font-weight: 600; font-size: 13px; color: var(--text-muted); }
input, select, button { font: inherit; color: var(--text); }
input, select {
  width: 100%;
  height: 42px;
  padding: 0 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
  transition: border-color .15s, box-shadow .15s;
  font-size: 14px;
}
input::placeholder { color: var(--text-muted); opacity: .7; }
input:focus, select:focus { outline: none; border-color: var(--primary); box-shadow: var(--ring); }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  height: 42px; padding: 0 16px;
  border: 1px solid transparent; border-radius: var(--radius-sm);
  background: var(--primary); color: var(--primary-text);
  font-weight: 600; font-size: 14px; cursor: pointer; white-space: nowrap;
  text-decoration: none;
  transition: background .15s, transform .05s, box-shadow .15s, border-color .15s;
}
.btn:hover { background: var(--primary-hover); }
.btn:active { transform: translateY(1px); }
.btn:focus-visible { outline: none; box-shadow: var(--ring); }
.btn:disabled { opacity: .55; cursor: not-allowed; }
.btn svg { width: 18px; height: 18px; flex: none; }
.btn-ghost { background: transparent; color: var(--text); border-color: var(--border); }
.btn-ghost:hover { background: var(--surface-3); }
.btn-soft { background: var(--primary-soft); color: var(--primary); }
.btn-soft:hover { background: var(--primary-soft); filter: brightness(.97); }
.btn-danger { background: transparent; color: var(--danger); border-color: var(--border); }
.btn-danger:hover { background: var(--danger-soft); border-color: transparent; }
.btn-sm { height: 34px; padding: 0 12px; font-size: 13px; }
.btn-icon { width: 42px; padding: 0; }
.btn-icon.btn-sm { width: 34px; }
.btn-block { width: 100%; }

/* ---------- Login ---------- */
.auth-page { display: grid; grid-template-columns: 1.1fr 1fr; min-height: 100vh; }
.auth-hero {
  position: relative; overflow: hidden;
  display: flex; flex-direction: column; justify-content: space-between;
  padding: 48px;
  color: #fff;
  background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 55%, #db2777 120%);
}
.auth-hero::after {
  content: ''; position: absolute; inset: auto -120px -160px auto;
  width: 420px; height: 420px; border-radius: 50%;
  background: rgba(255, 255, 255, .08);
}
.auth-hero h1 { font-size: 40px; line-height: 1.1; max-width: 460px; }
.auth-hero p { font-size: 16px; opacity: .85; max-width: 440px; margin-top: 14px; }
.hero-stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; max-width: 480px; position: relative; z-index: 1; }
.hero-stat { background: rgba(255, 255, 255, .12); border: 1px solid rgba(255, 255, 255, .18); border-radius: var(--radius); padding: 14px; backdrop-filter: blur(6px); }
.hero-stat strong { display: block; font-size: 22px; }
.hero-stat span { font-size: 12px; opacity: .8; }
.auth-panel { display: flex; flex-direction: column; padding: 32px; }
.auth-panel .topbar { display: flex; justify-content: flex-end; }
.auth-card { margin: auto; width: 100%; max-width: 400px; }
.auth-card h2 { font-size: 26px; margin-bottom: 6px; }
.auth-card .lead { color: var(--text-muted); margin-bottom: 28px; }
.google-btn {
  display: flex; align-items: center; justify-content: center; gap: 12px;
  width: 100%; height: 50px; border-radius: 12px;
  border: 1px solid var(--border-strong); background: var(--surface);
  color: var(--text); font-weight: 600; font-size: 15px; text-decoration: none;
  box-shadow: var(--shadow-sm); transition: box-shadow .15s, border-color .15s, transform .05s;
}
.google-btn:hover { box-shadow: var(--shadow); border-color: var(--primary); }
.google-btn:active { transform: translateY(1px); }
.google-btn svg { width: 20px; height: 20px; }
.auth-note {
  display: flex; gap: 10px; align-items: flex-start;
  margin-top: 20px; padding: 12px 14px;
  background: var(--surface-2); border: 1px solid var(--border); border-radius: 12px;
  font-size: 13px; color: var(--text-muted);
}
.auth-note svg { width: 18px; height: 18px; flex: none; color: var(--primary); margin-top: 1px; }
.alert { margin-top: 16px; padding: 12px 14px; border-radius: 12px; font-size: 14px; background: var(--danger-soft); color: var(--danger); }
.alert:empty { display: none; }
.auth-footer { text-align: center; font-size: 12px; color: var(--text-muted); }

.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; font-size: 17px; letter-spacing: -0.01em; position: relative; z-index: 1; }
.brand-mark {
  display: grid; place-items: center; width: 34px; height: 34px; border-radius: 10px;
  background: linear-gradient(135deg, var(--primary), var(--primary-2)); color: #fff;
  box-shadow: 0 6px 16px rgba(79, 70, 229, .35);
}
.auth-hero .brand-mark { background: rgba(255, 255, 255, .18); box-shadow: none; }
.brand-mark svg { width: 18px; height: 18px; }

/* ---------- App shell ---------- */
.app-header {
  position: sticky; top: 0; z-index: 20;
  background: color-mix(in srgb, var(--surface) 80%, transparent);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.app-header-inner { max-width: 1120px; margin: 0 auto; padding: 12px 24px; display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.header-actions { display: flex; align-items: center; gap: 8px; }
.user-chip { display: flex; align-items: center; gap: 10px; padding: 4px 12px 4px 4px; border: 1px solid var(--border); border-radius: 999px; background: var(--surface); }
.avatar {
  display: grid; place-items: center; width: 32px; height: 32px; border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--primary-2)); color: #fff;
  font-weight: 700; font-size: 13px;
}
.user-meta { line-height: 1.2; }
.user-meta strong { display: block; font-size: 13px; }
.user-meta span { font-size: 12px; color: var(--text-muted); }

.app-main { max-width: 1120px; margin: 0 auto; padding: 28px 24px 64px; }
.page-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 16px; margin-bottom: 20px; flex-wrap: wrap; }
.page-head p { color: var(--text-muted); margin-top: 4px; }

.tabs { display: inline-flex; gap: 4px; padding: 4px; background: var(--surface); border: 1px solid var(--border); border-radius: 12px; box-shadow: var(--shadow-sm); }
.tab {
  display: inline-flex; align-items: center; gap: 8px;
  height: 36px; padding: 0 14px; border: 0; border-radius: 9px;
  background: transparent; color: var(--text-muted); font-weight: 600; font-size: 14px; cursor: pointer;
  transition: background .15s, color .15s;
}
.tab svg { width: 16px; height: 16px; }
.tab:hover { color: var(--text); }
.tab.active { background: var(--primary-soft); color: var(--primary); }

.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow); }
.card-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 18px 20px; border-bottom: 1px solid var(--border); flex-wrap: wrap; }
.card-head p { font-size: 13px; color: var(--text-muted); margin-top: 2px; }
.card-body { padding: 20px; }
.card-foot { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 16px 20px; border-top: 1px solid var(--border); background: var(--surface-2); border-radius: 0 0 var(--radius) var(--radius); flex-wrap: wrap; }

.layout-split { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 20px; align-items: start; }
.stack { display: grid; gap: 20px; }

/* ---------- Stats ---------- */
.stat-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.stat { padding: 16px; border-radius: 12px; background: var(--surface-2); border: 1px solid var(--border); }
.stat-label { font-size: 12px; font-weight: 600; color: var(--text-muted); text-transform: uppercase; letter-spacing: .04em; }
.stat-value { font-size: 26px; font-weight: 800; letter-spacing: -0.02em; margin-top: 4px; font-variant-numeric: tabular-nums; }

.gpa-hero {
  position: relative; overflow: hidden; padding: 22px; border-radius: var(--radius);
  background: linear-gradient(135deg, #4f46e5, #7c3aed); color: #fff; box-shadow: var(--shadow-lg);
}
.gpa-hero::after { content: ''; position: absolute; right: -60px; top: -60px; width: 200px; height: 200px; border-radius: 50%; background: rgba(255, 255, 255, .1); }
.gpa-hero .stat-label { color: rgba(255, 255, 255, .8); }
.gpa-hero .gpa-number { font-size: 48px; font-weight: 800; letter-spacing: -0.03em; line-height: 1.1; margin: 6px 0 4px; font-variant-numeric: tabular-nums; }
.gpa-hero .gpa-sub { font-size: 13px; opacity: .85; }
.gpa-hero .stat-grid { grid-template-columns: 1fr 1fr; margin-top: 18px; position: relative; z-index: 1; }
.gpa-hero .stat { background: rgba(255, 255, 255, .12); border-color: rgba(255, 255, 255, .18); padding: 12px; }
.gpa-hero .stat-value { font-size: 20px; }

.scale-list { display: grid; grid-template-columns: 1fr; gap: 0; font-size: 13px; }
.scale-list div { display: flex; justify-content: space-between; padding: 6px 0; border-bottom: 1px dashed var(--border); }
.scale-list span:last-child { color: var(--text-muted); }

/* ---------- Tables ---------- */
.table-wrap { overflow-x: auto; }
.table { width: 100%; border-collapse: separate; border-spacing: 0; }
.table th { text-align: left; font-size: 12px; font-weight: 600; text-transform: uppercase; letter-spacing: .04em; color: var(--text-muted); padding: 10px 12px; border-bottom: 1px solid var(--border); background: var(--surface-2); }
.table th:first-child { border-top-left-radius: 10px; }
.table th:last-child { border-top-right-radius: 10px; }
.table td { padding: 10px 12px; border-bottom: 1px solid var(--border); font-size: 14px; vertical-align: middle; }
.table tbody tr:last-child td { border-bottom: 0; }
.table td input, .table td select { height: 38px; }
.table .num { text-align: right; font-variant-numeric: tabular-nums; }
.course-table td:first-child { padding-left: 0; }
.course-table td:last-child { padding-right: 0; width: 48px; }
.course-table th:first-child { padding-left: 12px; }
.empty-row td { text-align: center; color: var(--text-muted); padding: 22px; }

.course-row-index { color: var(--text-muted); font-size: 12px; font-weight: 600; width: 28px; text-align: center; }

/* ---------- Cumulative ---------- */
.term-picks { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 10px; }
.term-pick {
  position: relative; display: flex; align-items: center; gap: 12px; padding: 12px 14px;
  border: 1px solid var(--border); border-radius: 12px; background: var(--surface); cursor: pointer;
  transition: border-color .15s, background .15s;
}
.term-pick:hover { border-color: var(--border-strong); }
.term-pick input { position: absolute; opacity: 0; pointer-events: none; }
.term-pick .check {
  display: grid; place-items: center; width: 20px; height: 20px; flex: none;
  border: 2px solid var(--border-strong); border-radius: 6px; transition: all .15s;
}
.term-pick .check svg { width: 12px; height: 12px; color: #fff; opacity: 0; }
.term-pick:has(input:checked) { border-color: var(--primary); background: var(--primary-soft); }
.term-pick:has(input:checked) .check { background: var(--primary); border-color: var(--primary); }
.term-pick:has(input:checked) .check svg { opacity: 1; }
.term-pick:has(input:focus-visible) { box-shadow: var(--ring); }
.term-pick-name { font-weight: 600; font-size: 14px; }
.term-pick-meta { font-size: 12px; color: var(--text-muted); }

.inline-form { display: grid; grid-template-columns: minmax(0, 1fr) 100px 140px auto; gap: 10px; }

/* ---------- History ---------- */
.history-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 16px; }
.term-card { display: flex; flex-direction: column; padding: 18px; gap: 14px; cursor: pointer; transition: transform .15s, box-shadow .15s, border-color .15s; }
.term-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); border-color: var(--border-strong); }
.term-card-top { display: flex; justify-content: space-between; align-items: flex-start; gap: 8px; }
.term-card h3 { font-size: 16px; }
.term-card .date { font-size: 12px; color: var(--text-muted); margin-top: 2px; }
.term-card .gpa-pill { font-size: 22px; font-weight: 800; letter-spacing: -0.02em; font-variant-numeric: tabular-nums; }
.term-card .meta { display: flex; gap: 8px; flex-wrap: wrap; }
.term-card .actions { display: flex; gap: 8px; margin-top: auto; }
.term-card .actions .btn { flex: 1; }
.chip { display: inline-flex; align-items: center; gap: 6px; padding: 3px 10px; border-radius: 999px; background: var(--surface-3); color: var(--text-muted); font-size: 12px; font-weight: 600; }
.chip-primary { background: var(--primary-soft); color: var(--primary); }
.chip-success { background: var(--success-soft); color: var(--success); }
.chip-danger { background: var(--danger-soft); color: var(--danger); }
.chip-warning { background: color-mix(in srgb, var(--warning) 15%, transparent); color: var(--warning); }

.empty-state { text-align: center; padding: 48px 24px; color: var(--text-muted); }
.empty-state .icon { display: grid; place-items: center; width: 56px; height: 56px; margin: 0 auto 14px; border-radius: 16px; background: var(--primary-soft); color: var(--primary); }
.empty-state .icon svg { width: 26px; height: 26px; }
.empty-state h3 { color: var(--text); margin-bottom: 4px; }

.editing-banner { display: flex; align-items: center; gap: 10px; padding: 10px 14px; margin-bottom: 16px; border-radius: 12px; background: color-mix(in srgb, var(--warning) 12%, transparent); color: var(--warning); font-size: 14px; font-weight: 600; }

/* ---------- Toast ---------- */
.toast-stack { position: fixed; right: 20px; bottom: 20px; display: grid; gap: 10px; z-index: 100; }
.toast {
  display: flex; align-items: center; gap: 10px; min-width: 240px; max-width: 360px;
  padding: 12px 16px; border-radius: 12px; background: var(--text); color: var(--bg);
  box-shadow: var(--shadow-lg); font-size: 14px; font-weight: 500;
  animation: toast-in .2s ease-out;
}
.toast.success::before, .toast.error::before { content: ''; width: 8px; height: 8px; border-radius: 50%; flex: none; }
.toast.success::before { background: var(--success); }
.toast.error::before { background: var(--danger); }
@keyframes toast-in { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  .layout-split { grid-template-columns: 1fr; }
  .auth-page { grid-template-columns: 1fr; }
  .auth-hero { padding: 32px 24px; gap: 32px; }
  .auth-hero h1 { font-size: 30px; }
}
@media (max-width: 640px) {
  .app-header-inner, .app-main { padding-left: 16px; padding-right: 16px; }
  .user-meta { display: none; }
  .user-chip { padding: 4px; }
  .tabs { width: 100%; }
  .tab { flex: 1; justify-content: center; padding: 0 8px; }
  .tab span { display: none; }
  .stat-grid { grid-template-columns: 1fr 1fr; }
  .inline-form { grid-template-columns: 1fr 1fr; }
  .inline-form > :first-child { grid-column: 1 / -1; }
  .inline-form > .btn { grid-column: 1 / -1; }
  .hero-stats { grid-template-columns: 1fr 1fr 1fr; }
  .auth-panel { padding: 20px 16px; }
  .course-table thead { display: none; }
  .course-table, .course-table tbody, .course-table tr, .course-table td { display: block; width: 100%; }
  .course-table tr { display: grid; grid-template-columns: 1fr 1fr 42px; gap: 8px; padding: 10px 0; border-bottom: 1px solid var(--border); }
  .course-table td { padding: 0 !important; border: 0; }
  .course-table td.course-row-index { display: none; }
  .course-table td:nth-child(2) { grid-column: 1 / -1; }
}