:root {
    /* Designer Palette (Titanium / Slate) */
    --primary: #64748B;
    /* Slate 500 */
    --secondary: #94A3B8;
    /* Slate 400 */
    --accent: #38BDF8;
    /* Light Blue 400 */
    --accent-hover: #0284C7;
    /* Light Blue 600 */
    --background: #0F1219;
    /* Very Dark Slate */
    --surface: #1E293B;
    /* Slate 800 */

    --success: #10B981;
    /* Emerald 500 */
    --warning: #F59E0B;
    /* Amber 500 */
    --error: #EF4444;
    /* Red 500 */

    --glass-bg: rgba(30, 41, 59, 0.6);
    --glass-border: rgba(148, 163, 184, 0.15);

    --text-main: #F8FAFC;
    --text-muted: #94A3B8;
}

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

body {
    font-family: 'Inter', system-ui, sans-serif;
    background-color: var(--background);
    color: var(--text-main);
    min-height: 100vh;
    padding-bottom: 2rem;
}

.glass-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background: radial-gradient(circle at 15% 10%, rgba(56, 189, 248, 0.05), transparent 30%),
        radial-gradient(circle at 85% 90%, rgba(100, 116, 139, 0.08), transparent 40%);
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

header h1 {
    font-size: 2.25rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    background: linear-gradient(135deg, #FFF, var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

header p {
    color: var(--text-muted);
    font-size: 1.05rem;
    margin-top: 0.25rem;
}

/* Layout */
.layout {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 2rem;
    align-items: start;
}

.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.2);
    transition: opacity 0.3s ease, transform 0.3s ease;
}

/* Utilities */
.mt-2 {
    margin-top: 0.5rem;
}

.mt-3 {
    margin-top: 1rem;
}

.mt-4 {
    margin-top: 1.5rem;
}

.mb-2 {
    margin-bottom: 0.5rem;
}

.mb-3 {
    margin-bottom: 1rem;
}

.ml-2 {
    margin-left: 0.5rem;
}

.hidden {
    display: none !important;
}

.full-width {
    width: 100%;
}

.text-muted {
    color: var(--text-muted);
}

.text-accent {
    color: var(--accent) !important;
}

.text-success {
    color: var(--success) !important;
}

.text-sm {
    font-size: 0.85rem;
}

.text-xs {
    font-size: 0.75rem;
}

.font-mono {
    font-family: 'Fira Code', monospace;
}

.opacity-50 {
    opacity: 0.5;
    pointer-events: none;
}

h2 {
    font-size: 1.25rem;
    font-weight: 600;
}

h3 {
    font-size: 1.1rem;
    font-weight: 600;
}

.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

/* Controls Column */
.col-controls {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.step-panel {
    position: relative;
    overflow: hidden;
}

.step-panel.disabled {
    opacity: 0.4;
    pointer-events: none;
    filter: grayscale(100%);
}

.step-panel.disabled .step-badge {
    background: var(--primary);
    color: rgba(255, 255, 255, 0.5);
}

.step-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.step-badge {
    width: 32px;
    height: 32px;
    background: var(--accent);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.1rem;
    box-shadow: 0 2px 8px rgba(56, 189, 248, 0.4);
}

/* Forms */
.form-group label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-muted);
    font-weight: 500;
    margin-bottom: 0.4rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.input-control {
    width: 100%;
    padding: 0.7rem 1rem;
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-main);
    border-radius: 8px;
    outline: none;
    transition: 0.2s;
}

.input-control:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 2px rgba(56, 189, 248, 0.2);
}

.input-control[readonly] {
    background: rgba(0, 0, 0, 0.5);
    color: var(--secondary);
    border-style: dashed;
}

/* Scopes */
.scope-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.scope-tag {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.4rem 0.8rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 20px;
    font-size: 0.85rem;
    cursor: pointer;
    transition: 0.2s;
}

.scope-tag:hover {
    background: rgba(255, 255, 255, 0.1);
}

.scope-tag input {
    accent-color: var(--accent);
}

/* Buttons */
.btn {
    padding: 0.8rem 1.5rem;
    font-weight: 600;
    font-size: 0.95rem;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.primary-btn {
    background: var(--accent);
    color: #fff;
    box-shadow: 0 4px 12px rgba(56, 189, 248, 0.3);
}

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

.outline-btn {
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: var(--text-main);
}

.outline-btn:hover {
    border-color: var(--accent);
    background: rgba(56, 189, 248, 0.1);
}

/* Auth URL Box */
.param-box {
    background: rgba(0, 0, 0, 0.5);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 8px;
    padding: 1rem;
    color: var(--secondary);
    min-height: 50px;
    word-break: break-all;
    white-space: pre-wrap;
}

/* Sequence Diagram */
.sequence-diagram {
    position: relative;
    padding: 1rem 0;
    min-height: 200px;
}

.seq-actors {
    display: flex;
    justify-content: space-between;
    padding: 0 20px;
    margin-bottom: 20px;
}

.actor {
    text-align: center;
    width: 80px;
    position: relative;
    z-index: 2;
}

.actor-icon {
    width: 48px;
    height: 48px;
    background: var(--surface);
    border: 2px solid var(--primary);
    border-radius: 50%;
    margin: 0 auto 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.actor.client .actor-icon {
    border-color: var(--accent);
    color: var(--accent);
}

.actor.authz .actor-icon {
    border-color: var(--success);
    color: var(--success);
}

.actor-line {
    position: absolute;
    top: 48px;
    bottom: 0;
    left: 50%;
    width: 2px;
    background: rgba(255, 255, 255, 0.1);
    transform: translateX(-50%);
    z-index: 1;
}

.seq-messages {
    position: relative;
    min-height: 150px;
    padding-top: 10px;
}

.seq-msg {
    position: relative;
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    opacity: 0.3;
    transition: opacity 0.3s;
}

.seq-msg.active {
    opacity: 1;
}

.seq-arrow {
    position: absolute;
    top: 50%;
    height: 2px;
    background: var(--secondary);
    z-index: 2;
}

.seq-arrow::after {
    content: '';
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    border: 6px solid transparent;
}

.seq-msg.right .seq-arrow {
    left: calc(80px/2 + 20px);
    right: calc(80px/2 + 20px);
    background: var(--accent);
}

.seq-msg.right .seq-arrow::after {
    right: -4px;
    border-left-color: var(--accent);
}

.seq-msg.left .seq-arrow {
    left: calc(80px/2 + 20px);
    right: calc(80px/2 + 20px);
    background: var(--success);
}

.seq-msg.left .seq-arrow::after {
    left: -4px;
    border-right-color: var(--success);
}

.seq-msg.right.refresh .seq-arrow {
    background: var(--warning);
}

.seq-msg.right.refresh .seq-arrow::after {
    border-left-color: var(--warning);
}


.seq-label {
    position: absolute;
    top: -1.2rem;
    width: 100%;
    text-align: center;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-main);
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.8);
    left: 0;
}

/* Tokens Tabs */
.token-result-tabs {
    display: flex;
    gap: 2px;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 8px;
    padding: 4px;
}

.tab-btn {
    flex: 1;
    background: transparent;
    border: none;
    color: var(--text-muted);
    padding: 0.6rem;
    border-radius: 6px;
    font-weight: 500;
    cursor: pointer;
    transition: 0.2s;
    font-size: 0.9rem;
}

.tab-btn:hover {
    color: var(--text-main);
}

.tab-btn.active {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-main);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.tab-content {
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 8px;
}

.empty-state {
    padding: 3rem;
    text-align: center;
    color: var(--text-muted);
    font-style: italic;
    font-size: 0.9rem;
}

.token-inspect {
    padding: 1rem;
}

.jwt-seg {
    margin-bottom: 1rem;
}

.jwt-seg-title {
    font-size: 0.8rem;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 0.3rem;
    font-weight: 600;
}

.jwt-seg-content {
    font-family: 'Fira Code', monospace;
    font-size: 0.85rem;
    color: var(--accent);
    word-break: break-all;
    background: rgba(0, 0, 0, 0.5);
    padding: 0.8rem;
    border-radius: 6px;
    white-space: pre-wrap;
}

.jwt-seg.header .jwt-seg-content {
    color: var(--warning);
}

.jwt-seg.payload .jwt-seg-content {
    color: var(--success);
}

.jwt-seg.signature .jwt-seg-content {
    color: var(--error);
}


@media (max-width: 900px) {
    .layout {
        grid-template-columns: 1fr;
    }
}