/* ============================================================
   Spectrum 21 v3 — Sankalp Group Brand Design System
   Corporate Premium | Blue × Green Identity
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=DM+Serif+Display:ital@0;1&family=DM+Sans:opsz,wght@9..40,300;9..40,400;9..40,500&display=swap');

/* ── BRAND TOKENS ────────────────────────────────────────────── */
:root {
  /* Core Brand */
  --blue:          #1F3C88;
  --blue-mid:      #2356B4;
  --blue-light:    #2D9CDB;
  --green:         #27AE60;
  --green-dark:    #1E8449;

  /* Backgrounds */
  --bg:            #0B0F1A;
  --bg2:           #0E1422;
  --card:          #121826;
  --card-hover:    #162035;
  --border:        #1F2A3A;
  --border-subtle: rgba(31,60,136,0.3);

  /* Text */
  --text:          #FFFFFF;
  --text-2:        #A0AEC0;
  --text-3:        #4A5568;

  /* Gradients */
  --grad-panel:    linear-gradient(135deg, #1F3C88 0%, #27AE60 100%);
  --grad-panel-rev:linear-gradient(135deg, #1B3580 0%, #1E8449 100%);
  --grad-blue:     linear-gradient(135deg, #1F3C88, #2D9CDB);
  --grad-hero:     linear-gradient(180deg,
                     rgba(11,15,26,0.55) 0%,
                     rgba(11,15,26,0.15) 40%,
                     rgba(11,15,26,0.65) 100%);

  /* Glow */
  --glow-blue:     rgba(45,156,219,0.18);
  --glow-green:    rgba(39,174,96,0.18);
  --glow-panel:    rgba(45,156,219,0.12);

  /* Typography */
  --font-h:        'DM Serif Display', Georgia, serif;
  --font-b:        'DM Sans', system-ui, sans-serif;

  /* Motion */
  --ease:          cubic-bezier(0.4, 0, 0.2, 1);
  --ease-out:      cubic-bezier(0, 0, 0.2, 1);
  --spring:        cubic-bezier(0.34, 1.56, 0.64, 1);

  --max-w:         1380px;
}

/* ── RESET ───────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body { background: var(--bg); color: var(--text); font-family: var(--font-b); font-weight: 300; line-height: 1.65; overflow-x: hidden; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
button { cursor: pointer; border: none; background: none; font-family: inherit; color: inherit; }
::-webkit-scrollbar { width: 4px; }
::-webkit-scrollbar-track { background: var(--bg2); }
::-webkit-scrollbar-thumb { background: var(--blue); border-radius: 2px; }

/* ── PRELOADER ───────────────────────────────────────────────── */
#preloader {
  position: fixed; inset: 0; z-index: 9999;
  background: var(--bg);
  display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: 1.75rem;
  transition: opacity 0.8s var(--ease), visibility 0.8s;
}
#preloader.out { opacity: 0; visibility: hidden; pointer-events: none; }

.pl-mark {
  display: flex; align-items: center; gap: 1rem;
  opacity: 0;
  animation: fadeUp 0.7s 0.2s var(--ease-out) forwards;
}
.pl-icon {
  width: 42px; height: 42px;
  border-radius: 8px;
  background: var(--grad-panel);
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.pl-icon svg { width: 22px; height: 22px; }
.pl-name { font-family: var(--font-h); font-size: 1.5rem; font-weight: 400; letter-spacing: 0.05em; }
.pl-name span { color: var(--blue-light); }

.pl-track {
  width: 200px; height: 2px;
  background: var(--border);
  overflow: hidden;
  border-radius: 1px;
  opacity: 0;
  animation: fadeUp 0.7s 0.5s var(--ease-out) forwards;
}
.pl-fill {
  height: 100%;
  background: var(--grad-blue);
  border-radius: 1px;
  animation: fillBar 2s 0.7s var(--ease) forwards;
  width: 0;
}
.pl-label {
  font-size: 0.65rem; letter-spacing: 0.5em; text-transform: uppercase;
  color: var(--text-3); font-weight: 400;
  opacity: 0;
  animation: fadeUp 0.7s 0.7s var(--ease-out) forwards;
}
@keyframes fillBar { to { width: 100%; } }
@keyframes fadeUp { from { opacity:0; transform:translateY(14px); } to { opacity:1; transform:translateY(0); } }
@keyframes fadeDown { from { opacity:0; transform:translateY(-14px); } to { opacity:1; transform:translateY(0); } }

/* ── HERO ────────────────────────────────────────────────────── */
#hero {
  position: relative;
  height: 100vh; min-height: 620px;
  overflow: hidden;
}
#yt-bg {
  position: absolute; inset: 0;
  overflow: hidden; pointer-events: none;
  z-index: 0;
}
#yt-bg iframe {
  position: absolute;
  top: 50%; left: 50%;
  /* always covers viewport */
  width: max(100vw, 177.78vh);
  height: max(56.25vw, 100vh);
  transform: translate(-50%,-50%);
  border: none;
}
.hero-overlay {
  position: absolute; inset: 0; z-index: 1;
  background: var(--grad-hero);
}
/* Subtle blue tint layer */
.hero-tint {
  position: absolute; inset: 0; z-index: 1;
  background: rgba(11,15,26,0.35);
}

/* Top logo bar */
.hero-bar {
  position: absolute; top: 0; left: 0; right: 0;
  z-index: 3;
  padding: clamp(1.5rem, 3vw, 2.5rem) clamp(2rem, 5vw, 5rem);
  display: flex; align-items: center; justify-content: space-between;
}
.logo-wrap {
  display: flex; align-items: center; gap: 0.9rem;
  opacity: 0;
  animation: fadeDown 0.8s 2.8s var(--ease-out) forwards;
}
.logo-wrap img { height: clamp(36px, 4vw, 52px); width: auto; }
.logo-txt-name {
  font-family: var(--font-h);
  font-size: clamp(1rem, 2vw, 1.3rem); font-weight: 400;
  letter-spacing: 0.06em; color: var(--text);
  line-height: 1.2;
}
.logo-txt-sub {
  font-size: clamp(0.55rem, 1vw, 0.65rem);
  letter-spacing: 0.45em; text-transform: uppercase;
  color: var(--blue-light); font-weight: 400;
  display: block; margin-top: 0.15em;
}
.hero-divider {
  width: 1px; height: 40px;
  background: rgba(255,255,255,0.15);
  opacity: 0;
  animation: fadeDown 0.8s 2.8s var(--ease-out) forwards;
}

/* Scroll indicator */
.hero-scroll {
  position: absolute; bottom: 2.5rem; left: 50%;
  transform: translateX(-50%);
  z-index: 3;
  display: flex; flex-direction: column; align-items: center; gap: 0.6rem;
  opacity: 0;
  animation: fadeUp 0.8s 3.2s var(--ease-out) forwards;
}
.hero-scroll span {
  font-size: 0.6rem; letter-spacing: 0.5em; text-transform: uppercase;
  color: rgba(255,255,255,0.5); font-weight: 400;
}
.scroll-bar {
  width: 1px; height: 44px;
  background: linear-gradient(to bottom, rgba(255,255,255,0.6), transparent);
  animation: pulse 2s 3.2s infinite;
}
@keyframes pulse { 0%,100%{opacity:1;transform:scaleY(1)} 50%{opacity:0.4;transform:scaleY(0.6)} }

/* ── LAYOUT SHELL ────────────────────────────────────────────── */
.wrap { max-width: var(--max-w); margin: 0 auto; padding: 0 clamp(1.5rem, 5vw, 4.5rem); }

/* ── SECTION HEADER ──────────────────────────────────────────── */
.sec-header { margin-bottom: 3.5rem; }
.sec-label {
  display: inline-flex; align-items: center; gap: 0.6rem;
  font-size: 0.65rem; letter-spacing: 0.5em; text-transform: uppercase;
  color: var(--blue-light); font-weight: 500;
  margin-bottom: 1rem;
}
.sec-label::before {
  content: '';
  display: block; width: 20px; height: 2px;
  background: var(--blue-light); border-radius: 1px;
}
.sec-title {
  font-family: var(--font-h);
  font-size: clamp(2rem, 4vw, 3.2rem); font-weight: 400;
  letter-spacing: 0.01em; line-height: 1.15;
  color: var(--text);
}
.sec-title em { color: var(--blue-light); font-style: italic; }
.sec-desc {
  margin-top: 0.75rem;
  font-size: 0.9rem; color: var(--text-2); max-width: 520px; line-height: 1.8;
}
.sec-rule {
  width: 40px; height: 2px;
  background: var(--grad-blue);
  border-radius: 1px; margin: 1.5rem 0 0;
}

/* ── EXPERIENCES SECTION ─────────────────────────────────────── */
#experiences {
  padding: clamp(5rem, 8vw, 9rem) 0;
  background: var(--bg2);
  /* Subtle grid texture */
  background-image:
    linear-gradient(rgba(31,60,136,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(31,60,136,0.04) 1px, transparent 1px);
  background-size: 48px 48px;
}

.panels-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: 4px;
  overflow: hidden;
}

/* ── EXPERIENCE PANEL ────────────────────────────────────────── */
.exp-panel {
  position: relative;
  background: var(--card);
  padding: 2.75rem 2.25rem 2.5rem;
  cursor: pointer;
  overflow: hidden;
  display: flex; flex-direction: column;
  min-height: 360px;
  transition:
    background 0.45s var(--ease),
    transform  0.35s var(--spring);
  -webkit-tap-highlight-color: transparent;
}

/* Gradient reveal layer (hidden by default) */
.panel-gradient {
  position: absolute; inset: 0;
  background: var(--grad-panel);
  opacity: 0;
  transition: opacity 0.45s var(--ease);
  z-index: 0;
}

/* Subtle top accent line */
.panel-accent {
  position: absolute; top: 0; left: 0; right: 0;
  height: 2px;
  background: var(--grad-blue);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.5s var(--ease);
  z-index: 1;
}

/* Glow shimmer */
.panel-glow {
  position: absolute; bottom: -60px; right: -60px;
  width: 200px; height: 200px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(39,174,96,0.2) 0%, transparent 70%);
  pointer-events: none; z-index: 1;
  opacity: 0; transform: scale(0.6);
  transition: opacity 0.45s var(--ease), transform 0.45s var(--ease);
}

/* Hover state */
.exp-panel:hover { background: transparent; transform: scale(1.02); }
.exp-panel:hover .panel-gradient { opacity: 1; }
.exp-panel:hover .panel-accent { transform: scaleX(1); }
.exp-panel:hover .panel-glow { opacity: 1; transform: scale(1); }
.exp-panel:hover .panel-num { opacity: 0.2; }
.exp-panel:hover .panel-title,
.exp-panel:hover .panel-desc,
.exp-panel:hover .panel-link { color: rgba(255,255,255,0.95); }
.exp-panel:hover .panel-icon-wrap { border-color: rgba(255,255,255,0.3); background: rgba(255,255,255,0.1); }

/* Click */
.exp-panel:active { transform: scale(0.985); transition-duration: 0.12s; }

/* Panel number watermark */
.panel-num {
  font-family: var(--font-h);
  font-size: 4rem; font-weight: 400;
  color: rgba(31,60,136,0.25);
  line-height: 1;
  position: absolute; top: 1.5rem; right: 2rem;
  transition: opacity 0.35s, color 0.35s;
  z-index: 1;
  pointer-events: none;
}

/* Icon */
.panel-icon-wrap {
  width: 50px; height: 50px;
  border: 1px solid var(--border);
  border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  color: var(--blue-light);
  background: rgba(31,60,136,0.1);
  margin-bottom: 2rem; margin-top: auto;
  flex-shrink: 0;
  position: relative; z-index: 2;
  transition: border-color 0.35s, background 0.35s, color 0.35s;
}
.panel-icon-wrap svg { width: 22px; height: 22px; }

.panel-title {
  font-family: var(--font-h);
  font-size: clamp(1.15rem, 1.8vw, 1.4rem); font-weight: 400;
  letter-spacing: 0.01em; line-height: 1.3;
  color: var(--text);
  margin-bottom: 0.6rem;
  position: relative; z-index: 2;
  transition: color 0.3s;
}
.panel-desc {
  font-size: 0.8rem; color: var(--text-2); line-height: 1.75;
  flex: 1; margin-bottom: 1.75rem;
  position: relative; z-index: 2;
  transition: color 0.3s;
}
.panel-link {
  display: inline-flex; align-items: center; gap: 0.5rem;
  font-size: 0.72rem; letter-spacing: 0.25em; text-transform: uppercase;
  color: var(--blue-light); font-weight: 500;
  position: relative; z-index: 2;
  transition: color 0.3s, gap 0.3s var(--ease);
}
.exp-panel:hover .panel-link { gap: 0.75rem; }
.panel-link svg { width: 14px; height: 14px; transition: transform 0.3s var(--spring); }
.exp-panel:hover .panel-link svg { transform: translateX(4px); }

/* ── LOADING OVERLAY ─────────────────────────────────────────── */
#load-overlay {
  position: fixed; inset: 0; z-index: 5000;
  background: var(--bg);
  display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: 1.5rem;
  opacity: 0; visibility: hidden;
  transition: opacity 0.35s var(--ease), visibility 0.35s;
}
#load-overlay.show { opacity: 1; visibility: visible; }
.spin {
  width: 48px; height: 48px;
  border: 2px solid var(--border);
  border-top-color: var(--blue-light);
  border-radius: 50%;
  animation: spin 0.9s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.spin-label { font-size: 0.65rem; letter-spacing: 0.45em; text-transform: uppercase; color: var(--text-2); }

/* ── EXPERIENCE VIEWER ───────────────────────────────────────── */
#exp-viewer {
  position: fixed; inset: 0; z-index: 4500;
  background: var(--bg);
  display: flex; flex-direction: column;
  opacity: 0; visibility: hidden;
  transition: opacity 0.4s var(--ease), visibility 0.4s;
}
#exp-viewer.open { opacity: 1; visibility: visible; }
.vbar {
  height: 50px; flex-shrink: 0;
  background: var(--card);
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 1.5rem;
}
.vbar-title {
  font-size: 0.8rem; letter-spacing: 0.12em;
  color: var(--text-2); font-weight: 400;
}
.vbar-title strong { color: var(--blue-light); }
.vbar-acts { display: flex; align-items: center; gap: 0.5rem; }
.vbtn {
  padding: 0.35em 1em;
  border: 1px solid var(--border);
  font-size: 0.65rem; letter-spacing: 0.3em; text-transform: uppercase;
  color: var(--text-2); transition: all 0.2s;
}
.vbtn:hover { border-color: var(--blue-light); color: var(--blue-light); }
.vclose {
  width: 34px; height: 34px;
  border: 1px solid var(--border);
  display: flex; align-items: center; justify-content: center;
  color: var(--text-2); transition: all 0.2s;
}
.vclose:hover { border-color: #e74c3c; color: #e74c3c; }
.vframe-wrap { flex: 1; position: relative; }
#vframe { position: absolute; inset: 0; width: 100%; height: 100%; border: none; }
.vframe-loading {
  position: absolute; inset: 0;
  background: var(--bg);
  display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: 1.25rem;
  z-index: 2;
  transition: opacity 0.4s, visibility 0.4s;
}
.vframe-loading.gone { opacity: 0; visibility: hidden; pointer-events: none; }

/* ── FOOTER ──────────────────────────────────────────────────── */
footer {
  background: var(--bg2);
  border-top: 1px solid var(--border);
}
.footer-upper {
  padding: clamp(4rem, 6vw, 6rem) 0 clamp(3rem, 5vw, 5rem);
  border-bottom: 1px solid var(--border);
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: clamp(2rem, 4vw, 4rem);
}
.ft-brand-name {
  font-family: var(--font-h);
  font-size: 1.4rem; font-weight: 400;
  letter-spacing: 0.08em; color: var(--text);
  line-height: 1.2; margin-bottom: 0.2rem;
}
.ft-tagline {
  font-size: 0.65rem; letter-spacing: 0.45em;
  text-transform: uppercase; color: var(--blue-light);
  font-weight: 500; margin-bottom: 1.5rem;
}
.ft-about {
  font-size: 0.82rem; color: var(--text-3); line-height: 1.85;
  max-width: 300px;
}
.ft-col-label {
  font-size: 0.6rem; letter-spacing: 0.5em; text-transform: uppercase;
  color: var(--blue-light); font-weight: 500;
  margin-bottom: 1.25rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--border);
}
.ft-links { list-style: none; display: flex; flex-direction: column; gap: 0.55rem; }
.ft-links a {
  font-size: 0.82rem; color: var(--text-3); font-weight: 300;
  transition: color 0.2s, padding-left 0.25s;
  display: flex; align-items: center; gap: 0;
}
.ft-links a:hover { color: var(--blue-light); padding-left: 0.4rem; }
.ft-contact-row {
  display: flex; gap: 0.85rem; align-items: flex-start;
  margin-bottom: 1rem;
}
.ft-contact-icon {
  width: 30px; height: 30px; flex-shrink: 0;
  border: 1px solid var(--border);
  border-radius: 6px;
  display: flex; align-items: center; justify-content: center;
  color: var(--blue-light); margin-top: 0.1rem;
}
.ft-contact-icon svg { width: 13px; height: 13px; }
.ft-contact-text { font-size: 0.78rem; color: var(--text-3); line-height: 1.6; }
.ft-contact-text b { color: var(--text-2); font-weight: 400; display: block; font-size: 0.7rem; margin-bottom: 0.1rem; }

.footer-lower {
  padding: 1.25rem 0;
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 1rem;
}
.ft-copy { font-size: 0.72rem; color: var(--text-3); font-weight: 300; }
.ft-copy span { color: var(--blue-light); }
.ft-socials { display: flex; gap: 0.5rem; }
.soc-btn {
  width: 32px; height: 32px;
  border: 1px solid var(--border); border-radius: 6px;
  display: flex; align-items: center; justify-content: center;
  color: var(--text-3); transition: all 0.2s;
}
.soc-btn:hover { border-color: var(--blue-light); color: var(--blue-light); background: rgba(45,156,219,0.08); }
.soc-btn svg { width: 14px; height: 14px; }

/* ── SCROLL REVEAL ───────────────────────────────────────────── */
.reveal {
  opacity: 0; transform: translateY(28px);
  transition: opacity 0.75s var(--ease), transform 0.75s var(--ease);
}
.reveal.in { opacity: 1; transform: none; }
.rd1 { transition-delay: 0.1s; }
.rd2 { transition-delay: 0.18s; }
.rd3 { transition-delay: 0.26s; }
.rd4 { transition-delay: 0.34s; }

/* ── IDLE SCREEN ─────────────────────────────────────────────── */
#idle {
  position: fixed; inset: 0; z-index: 3500;
  background: var(--bg);
  display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: 2rem;
  opacity: 0; visibility: hidden;
  transition: opacity 0.8s var(--ease), visibility 0.8s;
}
#idle.show { opacity: 1; visibility: visible; }
.idle-mark { display: flex; align-items: center; gap: 1rem; }
.idle-icon {
  width: 52px; height: 52px; border-radius: 12px;
  background: var(--grad-panel);
  display: flex; align-items: center; justify-content: center;
}
.idle-icon svg { width: 26px; height: 26px; }
.idle-name { font-family: var(--font-h); font-size: 1.8rem; font-weight: 400; letter-spacing: 0.05em; }
.idle-name span { color: var(--blue-light); }
.idle-sub { font-size: 0.7rem; letter-spacing: 0.5em; text-transform: uppercase; color: var(--text-3); }
.idle-bar { width: 1px; height: 52px; background: linear-gradient(to bottom, var(--blue-light), transparent); animation: pulse 2s infinite; }

/* ── RESPONSIVE ──────────────────────────────────────────────── */
@media (max-width: 1100px) {
  .panels-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .panels-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-lower { flex-direction: column; text-align: center; }
  .exp-panel { min-height: 240px; padding: 2rem 1.75rem; }
}

/* ── SOUND TOGGLE BUTTON ─────────────────────────────────────── */
#sound-btn {
  position: absolute;
  bottom: 2.5rem;
  right: clamp(1.5rem, 4vw, 4rem);
  z-index: 3;
  width: 44px; height: 44px;
  border-radius: 50%;
  background: rgba(11,15,26,0.65);
  border: 1px solid rgba(255,255,255,0.15);
  color: rgba(255,255,255,0.75);
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: all 0.3s var(--ease);
  opacity: 0;
  animation: fadeUp 0.8s 3.4s var(--ease-out) forwards;
}
#sound-btn svg { width: 17px; height: 17px; }
#sound-btn:hover {
  background: rgba(31,60,136,0.75);
  border-color: rgba(45,156,219,0.5);
  color: #fff;
  transform: scale(1.08);
}
#sound-btn.active {
  background: rgba(31,60,136,0.85);
  border-color: var(--blue-light);
  color: var(--blue-light);
  box-shadow: 0 0 18px rgba(45,156,219,0.35);
}
#sound-btn.active::after {
  content: '';
  position: absolute; inset: -5px;
  border-radius: 50%;
  border: 1px solid rgba(45,156,219,0.4);
  animation: soundRing 1.8s infinite;
}
@keyframes soundRing {
  0%   { transform: scale(1);    opacity: 0.8; }
  100% { transform: scale(1.4);  opacity: 0; }
}