/* ============================================================
   Shamik Basu - Portfolio
   Single clean stylesheet, mobile-first, light + dark themes.
   ============================================================ */

:root {
  --bg: #ffffff;
  --bg-soft: #f6f7f9;
  --text: #1f2937;
  --text-muted: #5b6573;
  --heading: #0f172a;
  --border: #e6e8ec;
  --accent: #2563eb;
  --accent-soft: rgba(37, 99, 235, 0.08);
  --card: #ffffff;
  --shadow: 0 1px 2px rgba(15, 23, 42, 0.04), 0 8px 24px rgba(15, 23, 42, 0.05);
  --radius: 14px;
  --radius-sm: 10px;
  --maxw: 940px;
  --page-x: clamp(24px, 5vw, 36px);
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-head: 'Space Grotesk', var(--font-body);
}

html[data-theme="dark"] {
  --bg: #0b0f17;
  --bg-soft: #111725;
  --text: #c4ccd8;
  --text-muted: #8b95a5;
  --heading: #f1f5f9;
  --border: rgba(255, 255, 255, 0.09);
  --accent: #6ea8fe;
  --accent-soft: rgba(110, 168, 254, 0.12);
  --card: #121826;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 10px 30px rgba(0, 0, 0, 0.35);
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4 {
  font-family: var(--font-head);
  color: var(--heading);
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin: 0 0 0.5em;
}

:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 var(--page-x); }

.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--accent); color: #fff; padding: 10px 16px; border-radius: 0 0 8px 0; z-index: 200;
}
.skip-link:focus { left: 0; }

/* ===== Top bar (email, location, social) ===== */
.topbar {
  width: 100%;
  background: var(--bg-soft);
  border-bottom: 1px solid var(--border);
  font-size: 13px;
}
.topbar-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 7px var(--page-x);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}
.topbar-left,
.topbar-right {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}
.topbar-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--text-muted);
  font-weight: 500;
}
.topbar-item:hover { color: var(--accent); text-decoration: none; }
.topbar-item svg { flex-shrink: 0; opacity: 0.85; }
.topbar-connect {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 0;
  border: 0;
  background: none;
  font: inherit;
  font-weight: 600;
  color: var(--heading);
  cursor: pointer;
}
.topbar-connect:hover { color: var(--accent); }
.topbar-connect svg { color: var(--accent); }
.topbar-social {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.topbar-social a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  border-radius: 8px;
  color: var(--text-muted);
  border: 1px solid var(--border);
  background: var(--card);
}
.topbar-social a:hover {
  color: var(--accent);
  border-color: var(--accent);
  text-decoration: none;
}

/* ===== Floating calendar booking ===== */
.calendar-fab {
  position: fixed;
  bottom: 22px;
  right: 22px;
  z-index: 160;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 18px;
  border: 0;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  font-family: var(--font-body);
  cursor: pointer;
  box-shadow: 0 4px 20px rgba(37, 99, 235, 0.35);
  transition: transform 0.18s ease, filter 0.18s ease;
}
.calendar-fab:hover { filter: brightness(1.08); transform: translateY(-1px); }
.calendar-fab svg { flex-shrink: 0; }
.calendar-backdrop {
  position: fixed;
  inset: 0;
  z-index: 158;
  background: rgba(15, 23, 42, 0.45);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease;
}
.calendar-backdrop.open { opacity: 1; visibility: visible; }
.calendar-panel {
  position: fixed;
  bottom: 88px;
  right: 22px;
  z-index: 159;
  width: min(440px, calc(100vw - 44px));
  height: min(600px, calc(100vh - 110px));
  display: flex;
  flex-direction: column;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 16px 48px rgba(15, 23, 42, 0.18);
  overflow: hidden;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px) scale(0.98);
  transition: opacity 0.2s ease, visibility 0.2s ease, transform 0.2s ease;
}
.calendar-panel.open {
  opacity: 1;
  visibility: visible;
  transform: translateY(0) scale(1);
}
.calendar-panel-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-soft);
}
.calendar-panel-head h2 {
  margin: 0;
  font-size: 15px;
  font-weight: 600;
}
.calendar-fallback {
  display: inline-block;
  margin-top: 2px;
  font-size: 12px;
  font-weight: 500;
  color: var(--text-muted);
}
.calendar-fallback:hover { color: var(--accent); text-decoration: none; }
.calendar-close {
  width: 32px;
  height: 32px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  color: var(--heading);
  cursor: pointer;
}
.calendar-close:hover { border-color: var(--accent); color: var(--accent); }
.calendar-panel iframe,
.calendar-panel .calendar-frame {
  flex: 1;
  width: 100%;
  min-height: 0;
  border: 0;
  background: #fff;
}
body.calendar-open { overflow: hidden; }

/* ===== Navigation ===== */
.nav {
  position: sticky; top: 0; z-index: 100;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 12px var(--page-x);
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.nav-brand { font-family: var(--font-head); font-weight: 700; font-size: 17px; color: var(--heading); }
.nav-brand:hover { text-decoration: none; }
.nav-links { display: flex; align-items: center; gap: 22px; }
.nav-links a { color: var(--text-muted); font-size: 15px; font-weight: 500; }
.nav-links a:hover { color: var(--accent); text-decoration: none; }
.nav-actions { display: flex; align-items: center; gap: 10px; }

.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 9px 16px; border-radius: var(--radius-sm);
  font-size: 14px; font-weight: 600; cursor: pointer;
  border: 1px solid transparent; transition: all 0.18s ease;
}
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { filter: brightness(1.08); }
.btn-ghost { background: transparent; color: var(--heading); border-color: var(--border); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }
.btn-sm { padding: 7px 13px; font-size: 13px; }

.icon-btn {
  width: 38px; height: 38px; display: inline-flex; align-items: center; justify-content: center;
  border-radius: var(--radius-sm); border: 1px solid var(--border); background: var(--card);
  color: var(--heading); cursor: pointer;
}
.icon-btn:hover { border-color: var(--accent); color: var(--accent); }

.menu-toggle { display: none; }

/* ===== Sections ===== */
.section { padding: 64px 0; border-top: 1px solid var(--border); }
.section-label {
  text-transform: uppercase; letter-spacing: 0.14em; font-size: 12px; font-weight: 700;
  color: var(--accent); margin: 0 0 10px;
}
.section-title { font-size: 30px; margin: 0 0 8px; }
.section-sub { color: var(--text-muted); margin: 0 0 32px; max-width: 620px; }

/* ===== Hero ===== */
.hero { padding: 56px 0 40px; }
.hero-inner { display: grid; grid-template-columns: 1fr; gap: 18px; }
.hero-avatar {
  position: relative; overflow: hidden;
  width: 92px; height: 92px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-family: var(--font-head); font-weight: 700; font-size: 32px; color: #fff;
  background: linear-gradient(135deg, var(--accent), #7c3aed);
  box-shadow: var(--shadow);
}
.hero-avatar img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.hero h1 { font-size: clamp(34px, 6vw, 48px); margin: 0; }
.hero-tagline { font-size: clamp(18px, 3vw, 22px); color: var(--text-muted); margin: 6px 0 0; }
.hero-summary { max-width: 640px; margin: 8px 0 0; }
.hero-fun { max-width: 640px; margin: 10px 0 0; color: var(--text-muted); font-size: 15px; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 18px; }
.hero-meta { display: flex; flex-wrap: wrap; gap: 18px; margin-top: 16px; color: var(--text-muted); font-size: 14px; }
.hero-meta span { display: inline-flex; align-items: center; gap: 7px; }

.stat-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }
.stat-chip {
  background: var(--bg-soft); border: 1px solid var(--border); border-radius: 999px;
  padding: 7px 15px; font-size: 13px; font-weight: 600; color: var(--heading);
}

/* ===== Highlights slideshow ===== */
.slider { position: relative; border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); border: 1px solid var(--border); }
.slider-track { position: relative; }
.highlight-slide {
  display: none; position: relative; min-height: 280px;
  background: linear-gradient(135deg, #1e293b, #0f172a);
  color: #fff;
}
.highlight-slide.active { display: block; animation: fade 0.6s ease; }
@keyframes fade { from { opacity: 0; } to { opacity: 1; } }
.highlight-slide .slide-bg {
  position: absolute; inset: 0; background-color: #1e293b;
  background-size: cover; background-position: center; opacity: 0.5;
}
.highlight-slide .slide-body {
  position: relative; z-index: 1; padding: 40px 32px;
  display: flex; flex-direction: column; justify-content: flex-end; min-height: 280px;
  background: linear-gradient(to top, rgba(0,0,0,0.72), rgba(0,0,0,0.15));
}
.highlight-slide .slide-date { font-size: 13px; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase; opacity: 0.85; }
.highlight-slide h3 { color: #fff; font-size: clamp(20px, 4vw, 28px); margin: 6px 0 6px; }
.highlight-slide p { margin: 0; max-width: 560px; color: rgba(255,255,255,0.9); }
.highlight-slide a.slide-link { display: inline-flex; margin-top: 14px; color: #fff; font-weight: 600; }
.slider-dots { position: absolute; bottom: 14px; right: 18px; display: flex; gap: 8px; z-index: 2; }
.slider-dot { width: 9px; height: 9px; border-radius: 50%; border: none; background: rgba(255,255,255,0.45); cursor: pointer; padding: 0; }
.slider-dot.active { background: #fff; }

/* ===== Project cards (2 x 2 grid) ===== */
.project-grid {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px;
}
.project-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow); display: flex; flex-direction: column;
  transition: transform 0.18s ease, border-color 0.18s ease;
}
.project-card:hover { transform: translateY(-3px); border-color: var(--accent); }
.project-media {
  position: relative; aspect-ratio: 16 / 9; background: var(--bg-soft);
  display: flex; align-items: center; justify-content: center; border-bottom: 1px solid var(--border);
}
.video-embed { position: absolute; inset: 0; cursor: pointer; overflow: hidden; }
.video-embed .video-poster {
  position: absolute; inset: 0; background-size: cover; background-position: center;
  background-color: #0f172a;
  display: flex; align-items: center; justify-content: center; color: #fff;
}
.video-embed .play-badge {
  width: 56px; height: 56px; border-radius: 50%; background: rgba(0,0,0,0.55);
  display: flex; align-items: center; justify-content: center; border: 2px solid rgba(255,255,255,0.85);
}
.video-embed iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
.project-video {
  position: absolute; inset: 0; width: 100%; height: 100%;
  object-fit: cover; display: block; background: #0f172a;
}
.project-video-contain { object-fit: contain; background: var(--bg-soft); }
.video-mute-btn {
  position: absolute; bottom: 10px; left: 10px; z-index: 4;
  width: 36px; height: 36px; border-radius: 9px;
  display: flex; align-items: center; justify-content: center;
  color: #fff; background: rgba(0, 0, 0, 0.55); border: 1px solid rgba(255, 255, 255, 0.22);
  backdrop-filter: blur(4px); cursor: pointer;
  transition: background 0.18s ease, transform 0.18s ease;
}
.video-mute-btn:hover { background: var(--accent); transform: translateY(-1px); }
.video-mute-btn svg { width: 19px; height: 19px; }
.video-mute-btn .icon-unmuted { display: none; }
.video-mute-btn:not(.is-muted) .icon-muted { display: none; }
.video-mute-btn:not(.is-muted) .icon-unmuted { display: block; }
.case-video video {
  width: 100%; height: auto; display: block; background: #0f172a;
}
.media-fallback { color: var(--text-muted); font-size: 13px; text-align: center; padding: 0 16px; }
.project-body { padding: 20px 22px; display: flex; flex-direction: column; flex: 1; }
.project-award {
  align-self: flex-start; font-size: 11px; font-weight: 700; color: #b45309;
  background: rgba(245, 158, 11, 0.12); border: 1px solid rgba(245, 158, 11, 0.3);
  padding: 3px 9px; border-radius: 6px; margin-bottom: 10px;
}
html[data-theme="dark"] .project-award { color: #fbbf24; }
.project-card h3 { font-size: 19px; margin: 0 0 4px; }
.project-date { font-size: 13px; color: var(--text-muted); margin: 0 0 10px; }
.project-card p.tagline { margin: 0 0 14px; color: var(--text); }
.tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 16px; }
.tag {
  font-size: 12px; font-weight: 500; color: var(--accent);
  background: var(--accent-soft); border-radius: 6px; padding: 4px 9px;
}
/* Logo links in the top-right corner of the media */
.media-links { position: absolute; top: 10px; right: 10px; display: flex; gap: 8px; z-index: 3; }
.media-links a {
  width: 36px; height: 36px; border-radius: 9px; display: flex; align-items: center; justify-content: center;
  color: #fff; background: rgba(0, 0, 0, 0.55); border: 1px solid rgba(255, 255, 255, 0.22);
  backdrop-filter: blur(4px); transition: background 0.18s ease, transform 0.18s ease;
}
.media-links a:hover { background: var(--accent); transform: translateY(-1px); text-decoration: none; }
.media-links svg { width: 19px; height: 19px; }

/* Two main buttons in one row */
.project-actions { margin-top: auto; display: flex; gap: 10px; }
.project-actions .btn { flex: 1; justify-content: center; }
.btn-case { background: var(--heading); color: var(--bg); }
.btn-case:hover { filter: brightness(1.12); }
.btn-live {
  background: var(--accent); color: #fff; position: relative;
  animation: liveGlow 1.9s ease-in-out infinite;
}
.btn-live:hover { filter: brightness(1.08); }
.btn-live .live-dot {
  width: 8px; height: 8px; border-radius: 50%; background: #fff;
  box-shadow: 0 0 0 0 rgba(255, 255, 255, 0.9); animation: liveDot 1.9s ease-in-out infinite;
}
@keyframes liveGlow {
  0%, 100% { box-shadow: 0 0 6px 0 rgba(37, 99, 235, 0.55); }
  50% { box-shadow: 0 0 20px 5px rgba(37, 99, 235, 0.85); }
}
@keyframes liveDot {
  0%, 100% { box-shadow: 0 0 0 0 rgba(255, 255, 255, 0.85); }
  50% { box-shadow: 0 0 0 5px rgba(255, 255, 255, 0); }
}
@media (prefers-reduced-motion: reduce) {
  .btn-live, .btn-live .live-dot { animation: none; }
}

/* ===== Experience timeline ===== */
.timeline { display: flex; flex-direction: column; gap: 6px; }
.exp-item { padding: 18px 0; border-bottom: 1px solid var(--border); }
.exp-item:last-child { border-bottom: none; }
.exp-head { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 4px 16px; align-items: baseline; }
.exp-role { font-family: var(--font-head); font-weight: 600; font-size: 17px; color: var(--heading); }
.exp-dates { font-size: 13px; color: var(--text-muted); white-space: nowrap; }
.exp-company { font-size: 14px; color: var(--accent); font-weight: 500; margin: 2px 0 8px; }
.exp-item p { margin: 0; }

/* ===== Cards grid (education, leadership) ===== */
.cards { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; }
.info-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 22px 24px; box-shadow: var(--shadow);
}
.info-card h3 { font-size: 17px; margin: 0 0 4px; }
.info-card .muted { color: var(--text-muted); font-size: 14px; margin: 0 0 4px; }
.info-card .gpa { color: var(--accent); font-weight: 600; }

/* ===== Skills ===== */
.skills { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; }
.skill-group h3 { font-size: 15px; margin: 0 0 10px; }
.skill-pills { display: flex; flex-wrap: wrap; gap: 7px; }
.skill-pill {
  font-size: 13px; background: var(--bg-soft); border: 1px solid var(--border);
  border-radius: 999px; padding: 5px 12px; color: var(--text);
}

/* ===== Contact ===== */
.contact-links { display: flex; flex-direction: column; gap: 12px; max-width: 460px; }
.contact-card {
  display: flex; align-items: center; gap: 12px;
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 16px 18px; box-shadow: var(--shadow); color: var(--heading);
}
.contact-card:hover { border-color: var(--accent); text-decoration: none; }
.contact-card svg { color: var(--accent); flex-shrink: 0; }
.contact-card .c-label { font-size: 12px; color: var(--text-muted); }
.contact-card .c-value { font-weight: 600; font-size: 14px; word-break: break-word; }

/* ===== Footer ===== */
.footer {
  border-top: 1px solid var(--border); padding: 30px 0; color: var(--text-muted); font-size: 14px;
  display: flex; flex-wrap: wrap; gap: 8px 16px; align-items: center; justify-content: space-between;
}
.footer a { color: var(--text-muted); }
.footer a:hover { color: var(--accent); }

/* ===== Case-study (project detail) page ===== */
.case-hero { padding: 48px 0 24px; }
.case-back { font-size: 14px; font-weight: 600; display: inline-flex; gap: 6px; margin-bottom: 20px; }
.case-hero h1 { font-size: clamp(28px, 5vw, 40px); margin: 8px 0 8px; }
.case-hero .tagline { font-size: 18px; color: var(--text-muted); max-width: 640px; margin: 0 0 16px; }
.case-section { margin: 30px 0; }
.case-section h2 { font-size: 22px; }
.case-section ul { padding-left: 20px; }
.case-section li { margin-bottom: 8px; }
.case-video { aspect-ratio: 16 / 9; border-radius: var(--radius); overflow: hidden; border: 1px solid var(--border); position: relative; box-shadow: var(--shadow); margin: 8px 0 0; }
.case-video:has(> video) { aspect-ratio: auto; }
.case-figure {
  border-radius: var(--radius); overflow: hidden; border: 1px solid var(--border);
  box-shadow: var(--shadow); margin: 8px 0 0; background: var(--bg-soft);
}
.case-figure img { width: 100%; height: auto; display: block; }
.case-figure-caption {
  padding: 12px 16px; font-size: 13px; color: var(--text-muted); text-align: center;
  border-top: 1px solid var(--border);
}
.case-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.fact-card { background: var(--bg-soft); border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 16px 18px; }
.fact-card .fact-value { font-family: var(--font-head); font-weight: 700; font-size: 24px; color: var(--accent); }
.fact-card .fact-label { font-size: 13px; color: var(--text-muted); }

/* Project report download */
.report-card {
  display: flex; align-items: center; gap: 18px;
  background: var(--bg-soft); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px 22px; box-shadow: var(--shadow);
}
.report-card .report-icon {
  flex-shrink: 0; width: 48px; height: 48px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  background: var(--accent); color: #fff;
}
.report-card .report-icon svg { width: 26px; height: 26px; }
.report-card .report-info { flex: 1; min-width: 0; }
.report-card .report-info h2 { font-size: 18px; margin: 0 0 4px; }
.report-card .report-info p { margin: 0; font-size: 14px; color: var(--text-muted); }
.report-card .btn { flex-shrink: 0; }
.report-card .btn[aria-disabled="true"] { opacity: 0.5; pointer-events: none; }
@media (max-width: 600px) {
  .report-card { flex-direction: column; align-items: flex-start; }
  .report-card .btn { width: 100%; justify-content: center; }
}

/* ===== Mobile menu panel ===== */
.mobile-menu { display: none; }

/* ===== Responsive ===== */
@media (max-width: 760px) {
  .nav-links { display: none; }
  .menu-toggle { display: inline-flex; }
  .topbar-inner { justify-content: center; }
  .topbar-left { justify-content: center; }
  .topbar-item .topbar-text-email { display: none; }
  .calendar-fab span { display: none; }
  .calendar-fab { padding: 14px; border-radius: 50%; }
  .calendar-panel {
    bottom: 0;
    right: 0;
    left: 0;
    width: 100%;
    height: min(92vh, 700px);
    max-height: none;
    border-radius: var(--radius) var(--radius) 0 0;
    transform: translateY(100%);
  }
  .calendar-panel.open { transform: translateY(0); }
  .mobile-menu {
    display: block; max-height: 0; overflow: hidden; border-bottom: 1px solid transparent;
    transition: max-height 0.25s ease; background: var(--bg);
  }
  .mobile-menu.open { max-height: 360px; border-bottom: 1px solid var(--border); }
  .mobile-menu a {
    display: block; padding: 13px var(--page-x); color: var(--text); font-weight: 500;
    border-top: 1px solid var(--border);
  }
  .mobile-menu a:hover { text-decoration: none; color: var(--accent); }
  .cards, .skills { grid-template-columns: 1fr; }
  .case-grid { grid-template-columns: 1fr; }
  .section { padding: 48px 0; }
  .project-grid { grid-template-columns: 1fr; }
}