:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #dbeafe;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --border-focus: #2563eb;
    --error: #dc2626;
    --success: #16a34a;
    --bg: #f1f5f9;
    --white: #ffffff;
    --radius: 12px;
    --shadow: 0 10px 40px rgba(15, 23, 42, 0.08);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

.page {
    display: grid;
    grid-template-columns: 1fr 1.1fr;
    min-height: 100vh;
}

/* ---------- Sol panel (tanıtım) ---------- */
.brand-panel {
    background: linear-gradient(160deg, #1e3a8a 0%, #2563eb 60%, #3b82f6 100%);
    color: var(--white);
    display: flex;
    align-items: center;
    padding: 48px;
    position: relative;
    overflow: hidden;
}

.brand-panel::before {
    content: "";
    position: absolute;
    top: -80px;
    right: -80px;
    width: 320px;
    height: 320px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 50%;
}

.brand-panel::after {
    content: "";
    position: absolute;
    bottom: -120px;
    left: -60px;
    width: 280px;
    height: 280px;
    background: rgba(255, 255, 255, 0.06);
    border-radius: 50%;
}

.brand-inner {
    position: relative;
    z-index: 1;
    max-width: 420px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 56px;
}

.logo-mark {
    width: 44px;
    height: 44px;
    background: var(--white);
    color: var(--primary);
    border-radius: 10px;
    display: grid;
    place-items: center;
    font-weight: 800;
    font-size: 22px;
}

.logo-text {
    font-size: 20px;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.brand-title {
    font-size: 36px;
    font-weight: 800;
    line-height: 1.2;
    letter-spacing: -0.03em;
    margin-bottom: 16px;
}

.brand-subtitle {
    font-size: 16px;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 36px;
}

.feature-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.feature-list li {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 15px;
    color: rgba(255, 255, 255, 0.92);
}

.feature-icon {
    width: 24px;
    height: 24px;
    background: rgba(255, 255, 255, 0.18);
    border-radius: 50%;
    display: grid;
    place-items: center;
    font-size: 13px;
    flex-shrink: 0;
}

.brand-footer {
    margin-top: 48px;
    font-size: 14px;
    color: rgba(255, 255, 255, 0.8);
}

.brand-footer a {
    color: var(--white);
    font-weight: 600;
    text-decoration: underline;
}

/* ---------- Sağ panel (form) ---------- */
.form-panel {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 48px 32px;
}

.form-card {
    width: 100%;
    max-width: 560px;
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 40px;
}

.form-header {
    margin-bottom: 28px;
}

.form-header h2 {
    font-size: 26px;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 6px;
}

.form-header p {
    color: var(--text-muted);
    font-size: 15px;
}

fieldset {
    border: none;
    margin-bottom: 24px;
}

legend {
    font-size: 13px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-muted);
    margin-bottom: 14px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--border);
    width: 100%;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.form-group {
    margin-bottom: 18px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 7px;
}

.req {
    color: var(--error);
}

input[type="text"],
input[type="email"],
input[type="tel"],
input[type="password"],
select {
    width: 100%;
    padding: 12px 14px;
    font-size: 15px;
    font-family: inherit;
    color: var(--text);
    background: var(--white);
    border: 1.5px solid var(--border);
    border-radius: 10px;
    transition: border-color 0.15s, box-shadow 0.15s;
    outline: none;
}

input::placeholder {
    color: #94a3b8;
}

input:focus,
select:focus {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px var(--primary-light);
}

select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath fill='%2364748b' d='M6 8L0 0h12z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 14px center;
    padding-right: 36px;
    cursor: pointer;
}

/* Hata durumu */
.form-group.invalid input,
.form-group.invalid select {
    border-color: var(--error);
}

.form-group.invalid .error-msg {
    display: block;
}

.error-msg {
    display: none;
    color: var(--error);
    font-size: 13px;
    margin-top: 6px;
}

/* Şifre alanı */
.password-wrap {
    position: relative;
}

.toggle-pass {
    position: absolute;
    right: 10px;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    cursor: pointer;
    font-size: 16px;
    opacity: 0.6;
    padding: 4px;
}

.toggle-pass:hover {
    opacity: 1;
}

.pass-strength {
    height: 5px;
    background: var(--border);
    border-radius: 3px;
    margin-top: 8px;
    overflow: hidden;
}

.pass-bar {
    display: block;
    height: 100%;
    width: 0;
    border-radius: 3px;
    transition: width 0.25s, background 0.25s;
}

.pass-bar.weak   { width: 33%;  background: var(--error); }
.pass-bar.medium { width: 66%;  background: #f59e0b; }
.pass-bar.strong { width: 100%; background: var(--success); }

/* Checkbox */
.checkbox-group {
    margin-bottom: 14px;
}

.checkbox {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    font-size: 14px;
    font-weight: 400;
    color: var(--text-muted);
    cursor: pointer;
}

.checkbox input {
    width: 18px;
    height: 18px;
    margin-top: 1px;
    accent-color: var(--primary);
    cursor: pointer;
    flex-shrink: 0;
}

.checkbox a {
    color: var(--primary);
    font-weight: 600;
    text-decoration: none;
}

.checkbox a:hover {
    text-decoration: underline;
}

/* Buton */
.btn-submit {
    width: 100%;
    padding: 14px;
    font-size: 16px;
    font-weight: 700;
    font-family: inherit;
    color: var(--white);
    background: var(--primary);
    border: none;
    border-radius: 10px;
    cursor: pointer;
    margin-top: 8px;
    transition: background 0.15s, transform 0.05s;
}

.btn-submit:hover {
    background: var(--primary-dark);
}

.btn-submit:active {
    transform: scale(0.99);
}

.form-foot {
    text-align: center;
    font-size: 13px;
    color: var(--text-muted);
    margin-top: 16px;
}

.form-foot a {
    color: var(--primary);
    text-decoration: none;
}

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
    .page {
        grid-template-columns: 1fr;
    }

    .brand-panel {
        padding: 36px 32px;
    }

    .logo {
        margin-bottom: 28px;
    }

    .brand-title {
        font-size: 28px;
    }

    .feature-list {
        display: none;
    }

    .brand-footer {
        margin-top: 24px;
    }
}

@media (max-width: 540px) {
    .form-panel {
        padding: 24px 16px;
    }

    .form-card {
        padding: 24px 20px;
        box-shadow: none;
    }

    .form-row {
        grid-template-columns: 1fr;
        gap: 0;
    }

    .brand-panel {
        padding: 28px 24px;
    }

    .brand-title {
        font-size: 24px;
    }

    .form-header h2 {
        font-size: 22px;
    }
}