/* === Theme Variables === */
.hero{--hero-image: url('assets/csBanner.png');}

:root {
      --bg-color: #0c0c10;
      --text-color: #eef0f6;
      --header-bg: #0c0c10;
      --header-text: #eef0f6;
      --hero-text-color: #ff2e3c;
      --hero-overlay: rgba(12,12,16,0.72);
      --team-border: #ff2e3c;
      --extra-bg: #0c0c10;
      --extra-text: #eef0f6;
      --footer-bg: #0c0c10;
      --footer-text: #b4b7c9;
      --menu-bg: #0c0c10;
      --menu-text: #eef0f6;
      --menu-hover-bg: rgba(255,46,60,0.12);
      --menu-hover-text: #ff2e3c;
    }

    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      font-family: 'Noto Sans JP', sans-serif;
      background-color: var(--bg-color);
      color: var(--text-color);
      overflow-x: hidden;
      transition: background-color 0.6s ease, color 0.6s ease;
    }

    h1, h2, h3 { font-family: 'Oswald', sans-serif; text-transform: uppercase; letter-spacing: 2px; }
    a { text-decoration: none; color: inherit; transition: color 0.6s ease; }

    /* === Header & Nav === */
    header {
      background-color: var(--header-bg);
      color: var(--header-text);
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 15px 40px;
      box-shadow: 0 2px 10px rgba(0,0,0,0.1);
      position: relative;
      z-index: 100;
      transition: background-color 0.6s ease, color 0.6s ease;
    }

    .left-header { display: flex; align-items: center; gap: 15px; }
    .logo { font-size: 32px; font-weight: bold; letter-spacing: 4px; color: #e2e0e0; position: relative; z-index: 115; text-decoration: none; }
    .menu-button { font-size: 28px; background: none; border: none; color: #eef0f6; cursor: pointer; transition: transform 0.2s; z-index: 110; }
    .menu-button:hover { transform: scale(1.2); }

    nav ul { list-style: none; display: flex; gap: 25px; margin: 0; padding: 0; }
    nav ul li { transition: 0.3s; }
    nav ul li:hover { transform: scale(1.3); }
    @media (max-width: 900px) { nav ul { display: none; } }

    /* === Side Menu Panel === */
    .menu-box {
      position: fixed; top: 0; left: -250px; width: 250px; height: 100vh;
      background: var(--menu-bg); color: var(--menu-text);
      box-shadow: 3px 0 15px rgba(0,0,0,0.3);
      display: flex; flex-direction: column; padding-top: 20px;
      transition: left 0.6s cubic-bezier(0.68, -0.55, 0.27, 1.55), background-color 0.6s ease, color 0.6s ease;
      z-index: 105;
    }
    .menu-box.active { left: 0; }
    .menu-logo-placeholder { height: 60px; display: flex; align-items: center; justify-content: center; overflow: hidden; }
    .menu-box a { padding: 15px 20px; font-weight: 600; border-bottom: 1px solid rgba(255,255,255,0.2); color: var(--menu-text); transition: background 0.2s, color 0.2s; }
    .menu-box a:hover { background: var(--menu-hover-bg); color: var(--menu-hover-text); }

    /* === Hero Section === */
    .hero {
      background-image: url("assets/csBanner.png");
      background-size: cover;
      background-position: center;
      background-repeat: no-repeat;
      color: var(--hero-text-color);
      text-align: center;
      padding: 140px 20px;
      position: relative;
      transition: background-color 0.6s ease;
    }
    .hero::after {
      content: "";
      position: absolute; top: 0; left: 0; width: 100%; height: 100%;
      background-color: var(--hero-overlay); z-index: 0; transition: background-color 0.6s ease;
    }
    .hero-content { position: relative; z-index: 1; }
    .hero h1 { font-size: 60px; margin-bottom: 10px; color: var(--hero-text-color); text-shadow: 2px 2px 5px black; }
    .hero p { font-size: 22px; max-width: 600px; margin: auto; }

    /* === Teams Section === */
    .teams { text-align: center; padding: 80px 20px; background-color: #f9f9f9; }
    .teams h2 { color: #ff2e3c; font-size: 36px; margin-bottom: 40px; }
    .team-grid { display: flex; justify-content: center; flex-wrap: wrap; gap: 20px; }
    .team-card {
      background: var(--panel); border: 3px solid var(--team-border); border-radius: 10px;
      width: 250px; padding: 20px; transition: 0.6s ease, border-color 0.6s ease;
      opacity: 0; transform: translateY(50px);
      text-align: center;
    }
    .team-card.visible { opacity: 1; transform: translateY(0); }
    .team-card:hover { transform: translateY(-8px) scale(1.03); box-shadow: 0 4px 15px rgba(0,0,0,0.1); }
    .team-card img { width: 100%; border-radius: 8px; margin-bottom: 12px; }

    /* === Achievements Section === */
    #cs-achievements { padding: 80px 20px; text-align: center; }
    #cs-achievements ul { list-style: none; padding: 0; max-width: 600px; margin: auto; }
    #cs-achievements li { border-bottom: 1px solid rgba(0,0,0,0.1); padding: 10px 0; font-size: 18px; }

    /* === Upcoming Section === */
    #upcoming { background-color: var(--extra-bg); color: var(--extra-text); padding: 80px 20px; text-align: center; }
    #upcoming ul { list-style: none; padding: 0; max-width: 600px; margin: 20px auto 0; }
    #upcoming li { border-bottom: 1px solid rgba(255,255,255,0.2); padding: 10px 0; font-size: 18px; }

    /* === About Section === */
    #cs-about { padding: 80px 20px; max-width: 800px; margin: auto; text-align: center; line-height: 1.8; }

    /* === Extra Section === */
    .extra { background-color: var(--extra-bg); color: var(--extra-text); padding: 60px 20px; }
    .extra h2 { font-size: 26px; margin-bottom: 10px; }
    .extra-columns { display: flex; gap: 20px; justify-content: space-between; align-items: flex-start; flex-wrap: wrap; }
    .extra-left { flex: 2 1 0; min-width: 260px; }
    .extra-right { flex: 1 1 0; min-width: 220px; }
    .extra a { color: var(--extra-text); text-decoration: none; font-weight: bold; }

    footer { background: var(--footer-bg); color: var(--footer-text); text-align: center; padding: 15px; font-size: 14px; }

    /* === Dark Mode === */
    body.dark-mode {
      --bg-color: #0c0c10;
      --text-color: #eef0f6;
      --header-bg: #0c0c10;
      --header-text: #eef0f6;
      --hero-text-color: #ff2e3c;
      --hero-overlay: rgba(12,12,16,0.72);
      --team-border: #ff2e3c;
      --extra-bg: #0c0c10;
      --extra-text: #eef0f6;
      --footer-bg: #0c0c10;
      --footer-text: #b4b7c9;
      --menu-bg: #0c0c10;
      --menu-text: #eef0f6;
      --menu-hover-bg: rgba(255,46,60,0.12);
      --menu-hover-text: #ff2e3c;
    }

    @media (max-width: 900px) {
      nav ul { display: none; }
      .hero h1 { font-size: 40px; }
      .team-card { width: 90%; }
      .extra-columns { flex-direction: column; }
    }