/* ==========================================================================
   A.D.Stuart Associates - Modern Static Stylesheet (styles.css)
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Merriweather:wght@700&display=swap');

:root {
  --primary-navy: #0a1f35;
  --secondary-blue: #0284c7;
  --accent-cyan: #38bdf8;
  --accent-light: #e0f2fe;
  --bg-body: #f1f5f9;
  --bg-card: #ffffff;
  --text-main: #1e293b;
  --text-muted: #475569;
  --border-color: #e2e8f0;
  --shadow-sm: 0 1px 3px rgba(15, 41, 66, 0.06);
  --shadow-md: 0 6px 16px rgba(15, 41, 66, 0.08);
  --shadow-lg: 0 12px 28px rgba(15, 41, 66, 0.14);
  --radius: 12px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background-color: var(--bg-body);
  color: var(--text-main);
  line-height: 1.6;
  border-top: 4px solid var(--secondary-blue);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header & Navigation */
.site-header {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid var(--border-color);
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
}

.brand {
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 14px;
}

.brand-icon {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--primary-navy), var(--secondary-blue));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  box-shadow: var(--shadow-sm);
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.site-title {
  font-family: 'Merriweather', serif;
  font-size: 1.45rem;
  color: var(--primary-navy);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.site-subtitle {
  font-size: 0.75rem;
  color: var(--secondary-blue);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  margin-top: 1px;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 8px;
  align-items: center;
}

.nav-menu a {
  text-decoration: none;
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 9px 16px;
  border-radius: 8px;
  transition: all 0.2s ease;
}

.nav-menu a:hover {
  color: var(--secondary-blue);
  background: var(--accent-light);
}

.nav-menu a.active {
  background: var(--primary-navy);
  color: #ffffff;
}

/* Mobile Menu Button */
.menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 8px 12px;
  cursor: pointer;
  color: var(--primary-navy);
  font-size: 1.25rem;
}

/* Main Layout Grid */
.main-wrapper {
  display: grid;
  grid-template-columns: 1fr 310px;
  gap: 32px;
  margin: 36px auto;
  flex: 1;
}

/*Spruced Up Hero Banner with Acoustic SVG Artwork */
.hero-banner {
  background: radial-gradient(circle at 85% 20%, #0f3a61 0%, var(--primary-navy) 70%);
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 32px;
  box-shadow: var(--shadow-lg);
  color: #ffffff;
  position: relative;
  border: 1px solid rgba(56, 189, 248, 0.2);
}

.hero-art-bg {
  position: absolute;
  inset: 0;
  opacity: 0.35;
  pointer-events: none;
  overflow: hidden;
}

.hero-art-bg svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-banner-content {
  position: relative;
  z-index: 2;
  padding: 42px 36px;
  max-width: 720px;
}

.hero-badge {
  display: inline-block;
  background: rgba(56, 189, 248, 0.15);
  border: 1px solid rgba(56, 189, 248, 0.4);
  color: var(--accent-cyan);
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 5px 12px;
  border-radius: 99px;
  margin-bottom: 14px;
}

.hero-banner-content h1 {
  font-family: 'Merriweather', serif;
  font-size: 2rem;
  line-height: 1.3;
  margin-bottom: 12px;
  color: #ffffff;
}

.hero-banner-content p {
  color: #e2e8f0;
  font-size: 1.08rem;
  line-height: 1.6;
}

/* Content Area */
.content-box {
  background: var(--bg-card);
  padding: 34px;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-color);
}

.section-heading {
  font-size: 1.3rem;
  color: var(--primary-navy);
  margin-bottom: 22px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--accent-light);
  display: flex;
  align-items: center;
  gap: 10px;
}

.intro-lead {
  font-size: 1.05rem;
  color: var(--text-muted);
  margin-bottom: 22px;
}

/* Course Grid & Cards */
.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 18px;
}

.course-card {
  background: linear-gradient(to bottom right, #ffffff, #f8fafc);
  border: 1px solid var(--border-color);
  border-left: 4px solid var(--secondary-blue);
  border-radius: 10px;
  padding: 20px 22px;
  transition: all 0.25s ease;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.course-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--secondary-blue);
  background: #ffffff;
}

.course-card-header {
  display: flex;
  align-items: flex-start;
  gap: 14px;
}

.course-icon {
  flex-shrink: 0;
  width: 38px;
  height: 38px;
  border-radius: 8px;
  background: var(--accent-light);
  color: var(--secondary-blue);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.25s ease;
}

.course-card:hover .course-icon {
  background: var(--secondary-blue);
  color: #ffffff;
}

.course-card a.course-title {
  text-decoration: none;
  color: var(--primary-navy);
  font-weight: 700;
  font-size: 1.05rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  gap: 10px;
  line-height: 1.4;
}

.course-card a.course-title:hover {
  color: var(--secondary-blue);
}

.course-arrow {
  color: var(--secondary-blue);
  font-weight: bold;
  transition: transform 0.2s ease;
  flex-shrink: 0;
}

.course-card:hover .course-arrow {
  transform: translateX(4px);
}

.sub-courses {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed var(--border-color);
  list-style: none;
}

.sub-courses li {
  font-size: 0.9rem;
  color: var(--text-muted);
  padding: 4px 0 4px 18px;
  position: relative;
}

.sub-courses li::before {
  content: "▪";
  color: var(--secondary-blue);
  position: absolute;
  left: 2px;
  top: 3px;
}

/* Sidebar Contact Card

  /* ==========================================================================
   Accordion / Expandable Course Cards
   ========================================================================== */
.course-accordion {
    background: linear-gradient(to bottom right, #ffffff, #f8fafc);
    border: 1px solid var(--border-color);
    border-left: 4px solid var(--secondary-blue);
    border-radius: 10px;
    margin-bottom: 14px;
    overflow: hidden;
    transition: all 0.2s ease;
}

    .course-accordion:hover {
        box-shadow: var(--shadow-md);
        border-color: var(--secondary-blue);
    }

    .course-accordion summary {
        padding: 18px 22px;
        cursor: pointer;
        list-style: none;
    }

        .course-accordion summary::-webkit-details-marker {
            display: none;
        }

.summary-top {
    display: flex;
    align-items: center;
    gap: 14px;
}

.summary-title {
    font-weight: 700;
    font-size: 1.06rem;
    color: var(--primary-navy);
}

.course-accordion summary:hover .summary-title {
    color: var(--secondary-blue);
}

.course-accordion summary .toggle-icon {
    margin-left: auto;
    color: var(--secondary-blue);
    transition: transform 0.25s ease;
    font-size: 1.35rem;
    font-weight: 600;
    line-height: 1;
}

.course-accordion[open] summary .toggle-icon {
    transform: rotate(45deg);
}

.course-accordion[open] summary {
    border-bottom: 1px solid var(--border-color);
    background: #f8fafc;
}

.course-accordion summary .sub-courses {
    margin-top: 12px;
    margin-left: 52px;
    padding-top: 10px;
    border-top: 1px dashed var(--border-color);
}

.sub-courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 2px 18px;
}

/* Accordion Expanded Content */
.course-content {
    padding: 26px 28px;
    background: #ffffff;
    font-size: 0.96rem;
}

    .course-content h3,
    .course-content h4 {
        color: var(--primary-navy);
        margin: 24px 0 10px;
        font-size: 1.15rem;
    }

    .course-content p {
        margin-bottom: 14px;
    }

    .course-content a {
        color: var(--secondary-blue);
        font-weight: 600;
        text-decoration: none;
    }

        .course-content a:hover {
            text-decoration: underline;
        }

    .course-content ul.topicsList {
        margin: 8px 0 18px;
        padding-left: 0;
        list-style: none;
    }

        .course-content ul.topicsList ul.topicsList {
            margin: 6px 0 8px 18px;
        }

        .course-content ul.topicsList li {
            position: relative;
            padding-left: 18px;
            margin-bottom: 6px;
            color: var(--text-main);
        }

            .course-content ul.topicsList li::before {
                content: "▪";
                color: var(--secondary-blue);
                position: absolute;
                left: 0;
                top: 0;
            }

    .course-content ol {
        margin: 8px 0 18px 24px;
    }

        .course-content ol ol {
            margin: 6px 0 8px 22px;
        }

        .course-content ol li {
            margin-bottom: 8px;
        }

    .course-content hr.hr1 {
        border: 0;
        border-top: 1px dashed var(--border-color);
        margin: 20px 0;
    }

/* ==========================================================================
   Layout Width Lock, Skinnier Right Column, and Centered Profile Photo
   ========================================================================== */
html {
    overflow-y: scroll; /* Prevents scrollbar jump */
}

.container {
    width: 100%;
    max-width: 1240px; /* Slightly wider overall container */
}

.main-wrapper {
    width: 100%;
    grid-template-columns: minmax(0, 1fr) 230px; /* Bigger middle column, skinnier right column */
    gap: 28px;
}

.sidebar-card {
    padding: 22px 18px;
    display: flex;
    flex-direction: column;
    align-items: center; /* Centers everything horizontally in the right column */
    text-align: center;
}

    .sidebar-card h3 {
        width: 100%;
    }

.profile-img-wrap {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
    margin: 12px auto 0;
}

    .profile-img-wrap img {
        margin: 0 auto; /* Guarantees the image is centered */
        width: 135px;
        height: auto;
        display: block;
    }

@media (max-width: 900px) {
    .main-wrapper {
        grid-template-columns: 1fr;
    }
}
/* ==========================================================================
   Visual Polish: Engineering Grid Background, Animated Waves & Card Depth
   ========================================================================== */

/* 1. Subtle Engineering Blueprint Grid + Atmospheric Glow Background */
body {
    background-color: #eef4f8;
    background-image: radial-gradient(at 15% 0%, rgba(2, 132, 199, 0.10) 0px, transparent 50%), radial-gradient(at 85% 15%, rgba(10, 31, 53, 0.08) 0px, transparent 50%), linear-gradient(to right, rgba(2, 132, 199, 0.045) 1px, transparent 1px), linear-gradient(to bottom, rgba(2, 132, 199, 0.045) 1px, transparent 1px);
    background-size: 100% 100%, 100% 100%, 28px 28px, 28px 28px;
    background-attachment: fixed;
}

/* 2. Frosted Depth on Main Content Box & Sidebar */
.content-box,
.sidebar-card {
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.8);
    box-shadow: 0 10px 30px -5px rgba(10, 31, 53, 0.07), 0 0 0 1px rgba(2, 132, 199, 0.08);
}

/* 3. Interactive Glow & Lift on Course Accordions */
.course-accordion {
    background: #ffffff;
    border: 1px solid #e2e8f0;
    border-left: 5px solid var(--secondary-blue);
    box-shadow: 0 2px 5px rgba(10, 31, 53, 0.03);
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

    .course-accordion:hover {
        transform: translateX(4px);
        border-left-color: var(--primary-navy);
        box-shadow: 0 6px 16px rgba(2, 132, 199, 0.12);
    }

    .course-accordion[open] {
        border-left-color: var(--primary-navy);
        box-shadow: 0 8px 24px rgba(10, 31, 53, 0.10);
    }

/* 4. Gentle Oscilloscope Pulse Animation on Hero Banner Waves */
@keyframes wavePulse {
    0%, 100% {
        transform: scaleY(1) translateY(0);
    }

    50% {
        transform: scaleY(1.12) translateY(-3px);
    }
}

.hero-art-bg svg path {
    transform-origin: center;
    animation: wavePulse 6s ease-in-out infinite;
}

    .hero-art-bg svg path:nth-of-type(2) {
        animation-delay: -2s;
        animation-duration: 8s;
    }

    .hero-art-bg svg path:nth-of-type(3) {
        animation-delay: -4s;
        animation-duration: 7s;
    }

/* ==========================================================================
   Video Demos Page - Modern Playlist & Player Styling
   ========================================================================== */
.playlist-menu {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 24px;
}

.lessonbutton {
    width: 100%;
    text-align: left;
    border: 1px solid var(--border-color);
    background: #ffffff;
    color: var(--primary-navy);
    padding: 14px 18px;
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    border-radius: 8px;
    border-left: 5px solid #cbd5e1;
    transition: all 0.2s ease;
}

    .lessonbutton:hover {
        border-color: var(--secondary-blue);
        border-left-color: var(--secondary-blue);
        transform: translateX(3px);
    }

    .lessonbutton.activebutton {
        background: linear-gradient(135deg, var(--primary-navy) 0%, var(--secondary-blue) 100%);
        color: #ffffff;
        border-color: var(--primary-navy);
        border-left: 5px solid var(--accent-cyan);
        box-shadow: var(--shadow-md);
    }

.video-player-card {
    background: var(--primary-navy);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    border: 1px solid rgba(56, 189, 248, 0.25);
}

.video-stage {
    background: #000000;
    width: 100%;
    display: flex;
    justify-content: center;
}

    .video-stage video {
        width: 100%;
        max-height: 460px;
        display: block;
        outline: none;
    }

.video-now-playing {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 14px 20px;
    background: #102a45;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    flex-wrap: wrap;
    gap: 12px;
}

.now-playing-info {
    display: flex;
    align-items: center;
    gap: 12px;
}

.now-playing-badge {
    background: rgba(56, 189, 248, 0.2);
    color: var(--accent-cyan);
    font-size: 0.72rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    padding: 4px 10px;
    border-radius: 99px;
}

.now-playing-title {
    color: #ffffff;
    font-weight: 600;
    font-size: 1rem;
}

.video-Step-controls {
    display: flex;
    gap: 8px;
}

.video-nav-btn {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: #ffffff;
    padding: 6px 14px;
    border-radius: 6px;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s ease;
}

    .video-nav-btn:hover {
        background: var(--secondary-blue);
        border-color: var(--secondary-blue);
    }

.video-playlist-list {
    list-style: none;
    margin: 0;
    padding: 0;
    background: #ffffff;
}

    .video-playlist-list li {
        display: flex;
        align-items: center;
        gap: 12px;
        padding: 13px 20px;
        border-bottom: 1px solid var(--border-color);
        cursor: pointer;
        font-size: 0.95rem;
        color: var(--text-main);
        transition: background 0.15s ease;
    }

        .video-playlist-list li:last-child {
            border-bottom: none;
        }

        .video-playlist-list li:hover {
            background: var(--accent-light);
        }

        .video-playlist-list li.active-track {
            background: #e0f2fe;
            color: var(--primary-navy);
            font-weight: 700;
            border-left: 4px solid var(--secondary-blue);
        }

.track-play-icon {
    font-size: 0.8rem;
    color: var(--secondary-blue);
}
/* ==========================================================================
   Big Centered Play Button Overlay on Video Player
   ========================================================================== */
.video-stage {
    position: relative;
    cursor: pointer;
}

.big-play-btn {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 84px;
    height: 84px;
    border-radius: 50%;
    background: rgba(2, 132, 199, 0.88);
    border: 3px solid #ffffff;
    color: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.5);
    transition: all 0.25s ease;
    z-index: 10;
}

    .big-play-btn svg {
        width: 36px;
        height: 36px;
        margin-left: 5px; /* Optically centers the play triangle */
        fill: currentColor;
    }

.video-stage:hover .big-play-btn {
    background: var(--primary-navy);
    border-color: var(--accent-cyan);
    transform: translate(-50%, -50%) scale(1.08);
    box-shadow: 0 10px 30px rgba(56, 189, 248, 0.4);
}

.big-play-btn.hidden {
    opacity: 0;
    pointer-events: none;
    transform: translate(-50%, -50%) scale(0.85);
}