/* ===== style.css — GradePath Glass Morphism UI ===== */

/* ===== GLASS VARIABLES ===== */
:root {
  --glass-bg: rgba(255, 255, 255, 0.25);
  --glass-bg-strong: rgba(255, 255, 255, 0.55);
  --glass-bg-nav: rgba(255, 255, 255, 0.72);
  --glass-border: rgba(255, 255, 255, 0.35);
  --glass-border-strong: rgba(255, 255, 255, 0.5);
  --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.06);
  --glass-shadow-hover: 0 12px 40px rgba(0, 0, 0, 0.10);
  --blur-sm: blur(8px);
  --blur-md: blur(16px);
  --blur-lg: blur(24px);
  --primary: #2F6FED;
  --primary-light: rgba(47, 111, 237, 0.12);
  --primary-glow: rgba(47, 111, 237, 0.2);
  --success: #1E9E62;
  --danger: #D64545;
  --warning: #f1c40f;
  --text: #1A1A1A;
  --text-secondary: #555;
  --text-muted: #888;
  --bg-gradient-1: #e8edf5;
  --bg-gradient-2: #f0eef6;
  --bg-gradient-3: #e8f0f2;
}

/* ===== RESET & BASE ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: linear-gradient(135deg, var(--bg-gradient-1), var(--bg-gradient-2), var(--bg-gradient-3));
  background-attachment: fixed;
}

/* Subtle animated background */
body::before {
  content: '';
  position: fixed;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(ellipse at 20% 50%, rgba(47, 111, 237, 0.04) 0%, transparent 50%),
              radial-gradient(ellipse at 80% 20%, rgba(30, 158, 98, 0.04) 0%, transparent 50%),
              radial-gradient(ellipse at 50% 80%, rgba(47, 111, 237, 0.03) 0%, transparent 50%);
  z-index: -1;
  animation: bgShift 20s ease-in-out infinite alternate;
}

@keyframes bgShift {
  0% { transform: translate(0, 0) rotate(0deg); }
  100% { transform: translate(-2%, -1%) rotate(2deg); }
}

a {
  color: var(--primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

img {
  max-width: 100%;
  height: auto;
}

/* ===== CONTAINER ===== */
.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 24px;
  width: 100%;
}

.container-narrow {
  max-width: 780px;
  margin: 0 auto;
  padding: 0 24px;
  width: 100%;
}

/* ===== GLASS MIXIN (shared via classes) ===== */
.glass {
  background: var(--glass-bg);
  backdrop-filter: var(--blur-md);
  -webkit-backdrop-filter: var(--blur-md);
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
}

.glass-strong {
  background: var(--glass-bg-strong);
  backdrop-filter: var(--blur-md);
  -webkit-backdrop-filter: var(--blur-md);
  border: 1px solid var(--glass-border-strong);
  box-shadow: var(--glass-shadow);
}

/* ===== NAVBAR ===== */
.navbar {
  background: var(--glass-bg-nav);
  backdrop-filter: var(--blur-lg);
  -webkit-backdrop-filter: var(--blur-lg);
  border-bottom: 1px solid var(--glass-border-strong);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
}

.navbar-brand:hover {
  text-decoration: none;
}

.navbar-logo {
  width: 36px;
  height: 36px;
  flex-shrink: 0;
  filter: drop-shadow(0 2px 4px rgba(0,0,0,0.1));
}

.navbar-brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.navbar-brand-name {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.5px;
}

.navbar-brand-name span {
  background: linear-gradient(135deg, var(--primary), var(--success));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.navbar-brand-tagline {
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 400;
}

/* GitHub Stars Badge */
.github-stars {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 5px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  color: #333;
  background: rgba(255,255,255,0.6);
  backdrop-filter: blur(4px);
  border: 1px solid rgba(0,0,0,0.08);
  text-decoration: none;
  transition: all 0.2s;
  white-space: nowrap;
}

.github-stars:hover {
  background: rgba(255,255,255,0.9);
  transform: translateY(-1px);
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  text-decoration: none;
}

.github-stars .star-icon {
  width: 14px;
  height: 14px;
  color: #f1c40f;
}

.github-stars .star-count {
  font-variant-numeric: tabular-nums;
}

.github-stars .star-label {
  color: var(--text-muted);
  font-weight: 400;
  display: none;
}

@media (min-width: 480px) {
  .github-stars .star-label {
    display: inline;
  }
}

.navbar-links {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
}

.navbar-links li a {
  display: flex;
  align-items: center;
  gap: 5px;
  padding: 8px 14px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.2s;
}

.navbar-links li a:hover {
  background: var(--primary-light);
  color: var(--primary);
  text-decoration: none;
  backdrop-filter: blur(4px);
}

.navbar-links li a.active {
  background: rgba(47, 111, 237, 0.15);
  color: var(--primary);
  font-weight: 600;
  backdrop-filter: blur(4px);
  box-shadow: 0 0 0 1px rgba(47, 111, 237, 0.08);
}

.navbar-links li a.cta-btn {
  background: linear-gradient(135deg, var(--primary), #1e5fd4);
  color: #fff;
  padding: 8px 18px;
  font-weight: 600;
  margin-left: 6px;
  box-shadow: 0 2px 8px rgba(47, 111, 237, 0.25);
}

.navbar-links li a.cta-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(47, 111, 237, 0.35);
  background: linear-gradient(135deg, #1e5fd4, #184bb5);
}

/* Hamburger */
.navbar-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: rgba(255,255,255,0.5);
  backdrop-filter: blur(4px);
  border: 1px solid var(--glass-border);
  cursor: pointer;
  padding: 10px;
  min-height: 44px;
  min-width: 44px;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
}

.navbar-toggle span {
  display: block;
  width: 22px;
  height: 2.5px;
  background: var(--text);
  border-radius: 2px;
  transition: all 0.3s;
}

.navbar-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.navbar-toggle.active span:nth-child(2) {
  opacity: 0;
}

.navbar-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ===== MAIN ===== */
main {
  flex: 1;
  padding: 36px 0 60px;
}

/* ===== PAGE HEADER ===== */
.page-header {
  text-align: center;
  margin-bottom: 36px;
}

.page-header h1 {
  font-size: 32px;
  font-weight: 800;
  color: var(--text);
  margin-bottom: 10px;
  letter-spacing: -0.5px;
}

.page-header p {
  font-size: 16px;
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto;
}

/* ===== SECTION TITLES ===== */
.section-title {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text);
}

.section-subtitle {
  font-size: 15px;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

/* ===== HERO (HOME) ===== */
.hero {
  text-align: center;
  padding: 50px 0 40px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(47, 111, 237, 0.12);
  backdrop-filter: blur(8px);
  color: var(--primary);
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 20px;
  border: 1px solid rgba(47, 111, 237, 0.15);
}

.hero h1 {
  font-size: 42px;
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -1px;
  margin-bottom: 16px;
  color: var(--text);
}

.hero h1 span {
  background: linear-gradient(135deg, var(--primary), var(--success));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto 32px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}

.hero-actions .btn {
  padding: 14px 32px;
  font-size: 16px;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 40px;
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid var(--glass-border);
  flex-wrap: wrap;
}

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

.hero-stat-value {
  font-size: 28px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary), var(--success));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-stat-label {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 2px;
}

/* ===== FEATURES GRID ===== */
.features-section {
  padding: 50px 0;
}

.features-section .section-title {
  text-align: center;
  margin-bottom: 8px;
}

.features-section .section-subtitle {
  text-align: center;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 32px;
}

.feature-card {
  background: var(--glass-bg-strong);
  backdrop-filter: var(--blur-sm);
  -webkit-backdrop-filter: var(--blur-sm);
  border-radius: 12px;
  padding: 28px 24px;
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
  transition: all 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--glass-shadow-hover);
  border-color: var(--glass-border-strong);
  background: rgba(255, 255, 255, 0.65);
}

.feature-icon {
  font-size: 32px;
  margin-bottom: 14px;
}

.feature-card h3 {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text);
}

.feature-card p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ===== SCALE SELECTOR ===== */
.scale-section {
  background: var(--glass-bg-strong);
  backdrop-filter: var(--blur-sm);
  -webkit-backdrop-filter: var(--blur-sm);
  border-radius: 12px;
  padding: 24px;
  margin-bottom: 24px;
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
}

.scale-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
}

.scale-row label {
  font-weight: 600;
  font-size: 15px;
  min-width: 100px;
}

.scale-select {
  flex: 1;
  min-width: 200px;
  padding: 10px 14px;
  border: 1.5px solid var(--glass-border-strong);
  border-radius: 8px;
  font-size: 15px;
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(4px);
  color: var(--text);
  appearance: auto;
  cursor: pointer;
  transition: all 0.2s;
}

.scale-select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 22px;
  border: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
  min-height: 44px;
  font-family: inherit;
  text-decoration: none;
}

.btn:hover {
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), #1e5fd4);
  color: #fff;
  box-shadow: 0 2px 8px rgba(47, 111, 237, 0.25);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(47, 111, 237, 0.35);
  background: linear-gradient(135deg, #1e5fd4, #184bb5);
}

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

.btn-secondary {
  background: rgba(255, 255, 255, 0.6);
  color: var(--text);
  border: 1px solid var(--glass-border-strong);
  backdrop-filter: blur(4px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.85);
  transform: translateY(-1px);
  box-shadow: var(--glass-shadow);
}

.btn-outline {
  background: transparent;
  color: var(--primary);
  border: 2px solid var(--primary);
  backdrop-filter: blur(4px);
}

.btn-outline:hover {
  background: var(--primary-light);
  transform: translateY(-1px);
}

.btn-danger {
  background: rgba(255, 255, 255, 0.6);
  color: var(--danger);
  border: 1px solid rgba(214, 69, 69, 0.25);
  backdrop-filter: blur(4px);
  padding: 6px 12px;
  min-height: 36px;
  font-size: 13px;
}

.btn-danger:hover {
  background: rgba(214, 69, 69, 0.1);
  border-color: var(--danger);
}

.btn-success {
  background: linear-gradient(135deg, var(--success), #178a54);
  color: #fff;
  box-shadow: 0 2px 8px rgba(30, 158, 98, 0.25);
}

.btn-success:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(30, 158, 98, 0.35);
}

.btn-sm {
  padding: 6px 14px;
  min-height: 36px;
  font-size: 13px;
}

.btn-lg {
  padding: 14px 32px;
  font-size: 16px;
  min-height: 52px;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none !important;
  box-shadow: none !important;
}

/* ===== SEMESTER CARDS ===== */
.semesters-section {
  margin-bottom: 24px;
}

.semester-card {
  background: var(--glass-bg-strong);
  backdrop-filter: var(--blur-sm);
  -webkit-backdrop-filter: var(--blur-sm);
  border-radius: 12px;
  padding: 20px 24px;
  margin-bottom: 16px;
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
  transition: all 0.2s;
}

.semester-card:hover {
  box-shadow: var(--glass-shadow-hover);
  border-color: var(--glass-border-strong);
}

.semester-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--glass-border);
}

.semester-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--text);
}

.semester-sgpa {
  font-size: 15px;
  font-weight: 600;
  color: var(--success);
  background: rgba(30, 158, 98, 0.1);
  backdrop-filter: blur(4px);
  padding: 4px 14px;
  border-radius: 20px;
  border: 1px solid rgba(30, 158, 98, 0.15);
}

.semester-sgpa.empty {
  color: var(--text-muted);
  background: rgba(0,0,0,0.03);
  border-color: transparent;
}

/* ===== SUBJECT ROWS ===== */
.subject-rows {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.subject-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.35);
  backdrop-filter: blur(2px);
  transition: background 0.2s;
}

.subject-row:hover {
  background: rgba(255, 255, 255, 0.55);
}

.subject-row input,
.subject-row select {
  padding: 8px 12px;
  border: 1.5px solid var(--glass-border-strong);
  border-radius: 6px;
  font-size: 14px;
  background: rgba(255, 255, 255, 0.7);
  color: var(--text);
  font-family: inherit;
  transition: all 0.2s;
}

.subject-row input:focus,
.subject-row select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
  background: rgba(255, 255, 255, 0.9);
}

.subject-row input.input-error,
.subject-row select.input-error {
  border-color: var(--danger);
}

.subject-name-input {
  flex: 2;
  min-width: 120px;
}

.subject-credit-input {
  flex: 1;
  min-width: 70px;
  max-width: 100px;
}

.subject-grade-select {
  flex: 1;
  min-width: 90px;
  max-width: 120px;
}

.subject-row .btn-danger {
  flex-shrink: 0;
}

.subject-row .error-msg {
  width: 100%;
  font-size: 12px;
  color: var(--danger);
  padding-left: 4px;
}

.add-subject-btn {
  margin-top: 10px;
}

/* ===== RESULTS SECTION ===== */
.results-section {
  background: var(--glass-bg-strong);
  backdrop-filter: var(--blur-sm);
  -webkit-backdrop-filter: var(--blur-sm);
  border-radius: 12px;
  padding: 24px;
  margin-bottom: 24px;
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
}

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

.result-item {
  text-align: center;
  padding: 20px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(4px);
  border: 1px solid var(--glass-border);
}

.result-item.cgpa {
  background: rgba(47, 111, 237, 0.08);
  border: 1px solid rgba(47, 111, 237, 0.15);
}

.result-item .result-label {
  font-size: 14px;
  color: var(--text-secondary);
  font-weight: 500;
  margin-bottom: 6px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.result-item .result-value {
  font-size: 36px;
  font-weight: 800;
  color: var(--text);
  line-height: 1.2;
}

.result-item.cgpa .result-value {
  background: linear-gradient(135deg, var(--primary), #1e5fd4);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.result-item .result-value.empty {
  color: #bbb;
  font-weight: 400;
  -webkit-text-fill-color: #bbb;
  background: none;
}

/* ===== CUSTOM SCALE BUILDER ===== */
.custom-builder {
  background: var(--glass-bg-strong);
  backdrop-filter: var(--blur-md);
  -webkit-backdrop-filter: var(--blur-md);
  border-radius: 12px;
  padding: 24px;
  margin-bottom: 24px;
  border: 2px solid rgba(47, 111, 237, 0.3);
  box-shadow: 0 4px 24px rgba(47, 111, 237, 0.1);
  display: none;
}

.custom-builder.visible {
  display: block;
  animation: slideDown 0.3s ease;
}

@keyframes slideDown {
  from { opacity: 0; transform: translateY(-12px); }
  to { opacity: 1; transform: translateY(0); }
}

.custom-builder-title {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text);
}

.custom-grade-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}

.custom-grade-row input {
  padding: 8px 12px;
  border: 1.5px solid var(--glass-border-strong);
  border-radius: 6px;
  font-size: 14px;
  background: rgba(255, 255, 255, 0.6);
  color: var(--text);
  font-family: inherit;
}

.custom-grade-row .grade-label-input {
  flex: 1;
  min-width: 80px;
}

.custom-grade-row .grade-point-input {
  flex: 1;
  min-width: 80px;
  max-width: 120px;
}

.custom-builder-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--glass-border);
}

/* ===== EMPTY STATE ===== */
.empty-state {
  text-align: center;
  padding: 50px 20px;
  color: var(--text-muted);
}

.empty-state .empty-icon {
  font-size: 48px;
  margin-bottom: 16px;
  opacity: 0.5;
}

.empty-state .empty-title {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.empty-state .empty-desc {
  font-size: 14px;
  color: var(--text-muted);
  max-width: 400px;
  margin: 0 auto;
}

/* ===== PAGE SECTION (About/Contact) ===== */
.page-section {
  background: var(--glass-bg-strong);
  backdrop-filter: var(--blur-sm);
  -webkit-backdrop-filter: var(--blur-sm);
  border-radius: 12px;
  padding: 32px 28px;
  margin-bottom: 24px;
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
}

.page-section h2 {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text);
}

.page-section h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--text);
  margin-top: 24px;
}

.page-section h3:first-child {
  margin-top: 0;
}

.page-section p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 14px;
}

.page-section ul, 
.page-section ol {
  margin: 12px 0 16px 24px;
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.8;
}

.page-section li {
  margin-bottom: 6px;
}

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

.contact-info h3 {
  margin-top: 0;
}

.contact-info p {
  margin-bottom: 12px;
}

/* ===== SOCIAL LINKS ===== */
.social-links {
  display: flex;
  gap: 12px;
  margin-top: 16px;
  flex-wrap: wrap;
}

.social-link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 10px 20px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.2s;
  min-height: 44px;
  backdrop-filter: blur(4px);
}

.social-link:hover {
  text-decoration: none;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.social-link.x {
  background: rgba(0, 0, 0, 0.85);
  color: #fff;
  border: 1px solid rgba(255,255,255,0.1);
}

.social-link.x:hover { background: #000; }

.social-link.linkedin {
  background: rgba(0, 119, 181, 0.85);
  color: #fff;
  border: 1px solid rgba(255,255,255,0.1);
}

.social-link.linkedin:hover { background: #0077B5; }

.social-link.github {
  background: rgba(36, 41, 46, 0.85);
  color: #fff;
  border: 1px solid rgba(255,255,255,0.1);
}

.social-link.github:hover { background: #24292e; }

.social-link-icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

/* ===== DOCS / ARTICLE PAGE ===== */
.article-card {
  background: var(--glass-bg-strong);
  backdrop-filter: var(--blur-sm);
  -webkit-backdrop-filter: var(--blur-sm);
  border-radius: 12px;
  padding: 28px 32px;
  margin-bottom: 20px;
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
  scroll-margin-top: 80px;
}

.article-card h2 {
  font-size: 22px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
}

.article-card .article-meta {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 18px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--glass-border);
}

.article-card h3 {
  font-size: 17px;
  font-weight: 700;
  color: var(--text);
  margin: 20px 0 10px;
}

.article-card h4 {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  margin: 16px 0 8px;
}

.article-card p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 12px;
}

.article-card ul,
.article-card ol {
  margin: 10px 0 14px 24px;
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.8;
}

.article-card li {
  margin-bottom: 6px;
}

.article-card strong { color: var(--text); }

.article-card code {
  background: rgba(0,0,0,0.05);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 13px;
  color: var(--danger);
  backdrop-filter: blur(2px);
}

.article-card .note {
  background: rgba(241, 196, 15, 0.1);
  backdrop-filter: blur(4px);
  border-left: 4px solid var(--warning);
  padding: 12px 16px;
  border-radius: 0 8px 8px 0;
  margin: 16px 0;
  font-size: 14px;
  color: var(--text-secondary);
}

.article-card .tip {
  background: rgba(47, 111, 237, 0.08);
  backdrop-filter: blur(4px);
  border-left: 4px solid var(--primary);
  padding: 12px 16px;
  border-radius: 0 8px 8px 0;
  margin: 16px 0;
  font-size: 14px;
  color: var(--text-secondary);
}

/* ===== DOCS TOC ===== */
.docs-toc {
  background: var(--glass-bg-strong);
  backdrop-filter: var(--blur-sm);
  -webkit-backdrop-filter: var(--blur-sm);
  border-radius: 12px;
  padding: 24px 28px;
  margin-bottom: 24px;
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
}

.docs-toc h2 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 12px;
}

.docs-toc ol {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.docs-toc ol li a {
  display: block;
  padding: 8px 12px;
  border-radius: 8px;
  font-size: 14px;
  color: var(--primary);
  font-weight: 500;
  background: rgba(47, 111, 237, 0.06);
  backdrop-filter: blur(2px);
  transition: all 0.2s;
  text-decoration: none;
  border: 1px solid transparent;
}

.docs-toc ol li a:hover {
  background: rgba(47, 111, 237, 0.12);
  border-color: rgba(47, 111, 237, 0.1);
  text-decoration: none;
}

/* ===== ABOUT PAGE SPECIFIC ===== */
.about-values {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin: 20px 0;
}

.about-value {
  text-align: center;
  padding: 20px 12px;
  background: rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(4px);
  border-radius: 10px;
  border: 1px solid var(--glass-border);
}

.about-value .value-icon {
  font-size: 28px;
  margin-bottom: 8px;
}

.about-value h4 {
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 4px;
}

.about-value p {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 0;
}

/* ===== FOOTER ===== */
.site-footer {
  background: var(--glass-bg-nav);
  backdrop-filter: var(--blur-md);
  -webkit-backdrop-filter: var(--blur-md);
  border-top: 1px solid var(--glass-border-strong);
  padding: 24px 0;
  text-align: center;
  font-size: 14px;
  color: var(--text-muted);
}

.site-footer .built-by {
  font-weight: 600;
  color: var(--text-secondary);
}

.site-footer .footer-links {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-top: 8px;
  flex-wrap: wrap;
}

.site-footer .footer-links a {
  font-size: 13px;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s;
}

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

/* ================================================================
   TOAST NOTIFICATIONS
   ================================================================ */
.toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: 10px;
  max-width: 400px;
  width: calc(100% - 48px);
  pointer-events: none;
}

.toast {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 16px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(255, 255, 255, 0.4);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.10);
  transform: translateX(calc(100% + 48px));
  opacity: 0;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  pointer-events: auto;
  position: relative;
}

.toast.toast-visible {
  transform: translateX(0);
  opacity: 1;
}

.toast.toast-leaving {
  transform: translateX(calc(100% + 48px));
  opacity: 0;
}

.toast-icon {
  font-size: 18px;
  flex-shrink: 0;
  line-height: 1;
}

.toast-message {
  flex: 1;
  font-size: 14px;
  color: var(--text);
  line-height: 1.4;
}

.toast-close {
  background: none;
  border: none;
  font-size: 20px;
  color: var(--text-muted);
  cursor: pointer;
  padding: 0 2px;
  line-height: 1;
  flex-shrink: 0;
  transition: color 0.2s;
}

.toast-close:hover {
  color: var(--text);
}

/* Toast types */
.toast-success { border-left: 4px solid var(--success); }
.toast-error { border-left: 4px solid var(--danger); }
.toast-info { border-left: 4px solid var(--primary); }
.toast-warning { border-left: 4px solid var(--warning); }

/* ================================================================
   MODAL NOTIFICATIONS
   ================================================================ */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 10000;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.3);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
  padding: 24px;
}

.modal-overlay.modal-open {
  opacity: 1;
  visibility: visible;
}

.modal-dialog {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.5);
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.15);
  max-width: 460px;
  width: 100%;
  transform: scale(0.9) translateY(20px);
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  overflow: hidden;
}

.modal-open .modal-dialog {
  transform: scale(1) translateY(0);
}

.modal-header {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 20px 24px 0;
}

.modal-icon {
  font-size: 22px;
  flex-shrink: 0;
  line-height: 1;
}

.modal-title {
  flex: 1;
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
  margin: 0;
}

.modal-close {
  background: none;
  border: none;
  font-size: 24px;
  color: var(--text-muted);
  cursor: pointer;
  padding: 0;
  line-height: 1;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
  transition: all 0.2s;
}

.modal-close:hover {
  background: rgba(0,0,0,0.05);
  color: var(--text);
}

.modal-body {
  padding: 16px 24px 8px;
}

.modal-body p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
  margin: 0;
}

.modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  padding: 16px 24px 20px;
}

.modal-footer .btn {
  min-width: 80px;
}

/* Modal types */
.modal-success .modal-icon { color: var(--success); }
.modal-error .modal-icon { color: var(--danger); }
.modal-info .modal-icon { color: var(--primary); }
.modal-warning .modal-icon { color: var(--warning); }

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .container,
  .container-narrow {
    padding: 0 16px;
  }
  
  .navbar .container {
    height: 56px;
  }

  .navbar-toggle {
    display: flex;
  }

  .navbar-links {
    display: none;
    position: absolute;
    top: 56px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--glass-border-strong);
    padding: 8px 16px 16px;
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.08);
    gap: 2px;
  }

  .navbar-links.open {
    display: flex;
  }

  .navbar-links li a {
    width: 100%;
    padding: 12px 14px;
    font-size: 15px;
  }

  .navbar-links li a.cta-btn {
    margin-left: 0;
    margin-top: 4px;
    justify-content: center;
  }

  /* Hide github stars text on very small screens, keep the icon */
  .github-stars .star-label {
    display: none !important;
  }
  .github-stars .star-count {
    display: none;
  }
  .github-stars {
    padding: 6px 10px;
    font-size: 0;
  }
  .github-stars .star-icon {
    margin: 0;
  }

  .hero { padding: 30px 0; }
  .hero h1 { font-size: 30px; }
  .hero p { font-size: 16px; }
  .hero-stats { gap: 24px; }

  .features-grid { grid-template-columns: 1fr; gap: 16px; }
  .about-values { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; gap: 24px; }
  .page-header h1 { font-size: 26px; }

  .scale-section, .custom-builder, .results-section,
  .page-section, .article-card, .docs-toc { padding: 18px; }
  .semester-card { padding: 16px; }
  .results-grid { grid-template-columns: 1fr; gap: 12px; }
  .result-item .result-value { font-size: 28px; }

  .subject-row { padding: 8px; }
  .subject-name-input { flex: 1 1 100%; min-width: unset; }
  .subject-credit-input { flex: 1; min-width: 60px; }
  .subject-grade-select { flex: 1; min-width: 80px; }

  .scale-row { flex-direction: column; align-items: stretch; }
  .scale-row label { min-width: unset; }
  .scale-select { min-width: unset; }
  .semester-header { flex-direction: column; align-items: flex-start; }
  .social-links { flex-direction: column; }
  .social-link { justify-content: center; }

  .hero-actions { flex-direction: column; align-items: stretch; }
  .hero-actions .btn { justify-content: center; }

  .toast-container {
    bottom: 16px;
    right: 16px;
    max-width: none;
    width: calc(100% - 32px);
  }
}

@media (min-width: 769px) {
  .github-stars .star-count {
    display: inline;
  }
}

@media (max-width: 480px) {
  main { padding: 20px 0 30px; }
  .hero h1 { font-size: 26px; }
  .result-item { padding: 14px; }
  .result-item .result-value { font-size: 24px; }
  .btn { font-size: 13px; padding: 8px 14px; min-height: 40px; }
  .semester-title { font-size: 15px; }
  .page-header h1 { font-size: 22px; }
}

/* ===== MODAL FORM STYLES ===== */
.modal-form-group {
  margin-bottom: 16px;
}

.modal-form-group label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 6px;
}

.modal-form-group .form-input {
  width: 100%;
  padding: 10px 14px;
  border: 1.5px solid var(--glass-border-strong);
  border-radius: 8px;
  font-size: 15px;
  background: rgba(255, 255, 255, 0.7);
  color: var(--text);
  font-family: inherit;
  transition: all 0.2s;
}

.modal-form-group .form-input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
  background: rgba(255, 255, 255, 0.9);
}

.modal-form-group .form-input.input-error {
  border-color: var(--danger);
}

.modal-form-group .form-error {
  font-size: 13px;
  color: var(--danger);
  margin-top: 4px;
  display: none;
}

.modal-form-group .form-error.visible {
  display: block;
}

.form-hint {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 4px;
}

/* Grade preview table inside modal */
.grade-preview-table {
  width: 100%;
  border-collapse: collapse;
  margin: 12px 0 8px;
  border-radius: 8px;
  overflow: hidden;
}

.grade-preview-table th {
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-muted);
  padding: 8px 12px;
  text-align: left;
  background: rgba(0,0,0,0.02);
  border-bottom: 1px solid var(--glass-border);
}

.grade-preview-table td {
  padding: 8px 12px;
  font-size: 14px;
  color: var(--text);
  border-bottom: 1px solid var(--glass-border);
}

.grade-preview-table tr:last-child td {
  border-bottom: none;
}

.grade-preview-table .grade-label-cell {
  font-weight: 600;
}

.grade-preview-table .grade-point-cell {
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-weight: 600;
  color: var(--primary);
}

.grade-preview-table .grade-valid {
  color: var(--success);
  font-size: 12px;
}

.grade-preview-table .grade-duplicate {
  background: rgba(214, 69, 69, 0.06);
}

.grade-preview-table .grade-duplicate .grade-label-cell {
  color: var(--danger);
}

.grade-duplicate-badge {
  display: inline-block;
  padding: 1px 6px;
  border-radius: 4px;
  font-size: 10px;
  font-weight: 600;
  background: rgba(214, 69, 69, 0.1);
  color: var(--danger);
  margin-left: 4px;
  vertical-align: middle;
}

/* Validation summary */
.validation-summary {
  background: rgba(214, 69, 69, 0.06);
  border: 1px solid rgba(214, 69, 69, 0.15);
  border-radius: 8px;
  padding: 10px 14px;
  margin: 8px 0 4px;
}

.validation-summary p {
  font-size: 13px;
  color: var(--danger);
  margin: 0;
  line-height: 1.5;
}

.validation-summary.success {
  background: rgba(30, 158, 98, 0.06);
  border-color: rgba(30, 158, 98, 0.15);
}

.validation-summary.success p {
  color: var(--success);
}

/* Modal footer with disabled state handled */
.modal-footer .btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* ===== UTILITY ===== */
.hidden { display: none !important; }
.text-center { text-align: center; }
.mt-16 { margin-top: 16px; }
.mb-16 { margin-bottom: 16px; }
.mt-24 { margin-top: 24px; }
.mb-24 { margin-bottom: 24px; }